Excuse the Wall of Text
I honestly do not think it is as simple as "fear of being rejected". Indeed, there are many cases where it does apply, but it goes deeper... much deeper. The main rejection issue is not from a potential partner, realistically, it is from a society standpoint. We live in a world "ruled" by "breasts and bottoms"; considered standard. Anything that crosses that line, goes beyond the "normal" liking of these specific body parts, beyond "mommy and daddy" casual sex, is "abnormal". "You like feet?", "Tickling?", "BDSM?", etc... abnormal. A "fetish", an actual "problem" with your brain; a mental issue if you may (we all understand the wrong usage of such word, but think vanilla).
What does not help, as well as the uninformed vanilla public, is the community. Not TMF in particular; in general. Whenever a "foot fetishist" asks for a picture, or "one of us" ask someone, somewhere, if they are ticklish... well, let us break this down properly. In this internet dimension, if the words "Show your breasts" are seen, it ends there. They were seen and ignored. It is simply "another one of those trolls/pervs asking for boob pictures". In this scenario, there once was a "troll", a "perv". The End. Then we have... "Show your feet", "Feet plz", "I could suck those toes", etc etc... now we have a problem. "We have a 'creepy foot guy' ladies and gentlemen, red alert!". As of, equally bad; but "the creepy foot guy" is an "abnormality in the Matrix". See a pattern? Abnormal.
When someone asks a famous individual, or anyone with a small social influence "Are you ticklish? Where?", "How ticklish is (insert body part)?" we have different observing points. The tickling community is happy. Someone had the courage to ask, what a hero. If they get an answer, and said answer is positive, they become a legend. Now, the vanilla observing point is a bit more complex, I am afraid. Another red alert. Some may see the question "Are you ticklish" as playful. It can be cute. It can be foreplay. But also, out there, are people who are terrified of being tickled. To those, might as well ask "Would you like to be waterboarded?". It gets worse, oh so much worse when something along these lines is seen: "Now knock her out with (insert drug/liquid name), tie her down and tickle her until she screams". Some 'lees like to be pushed beyond a comfortable point; fair enough. The keyword is "some". As a 'ler, that sort of comment creeps me out. Have I "tickle tortured" a 'lee before? Yes, with their permission. Not only, also playfully. But that is on a whole new level. Psychopathic. Even if toned down to "tie her down and tickle her until she screams/pees/begs" to the vanillas reading, yes, those horrified vanillas, they read: "Torture". Not the playful sexual one. Actual terrifying abuse. In other words, the rotten apples stand out much more in any situation.
"Fetishes" in general are not seen with good eyes. Many of us here do not have fetishes. We can get aroused and climax through other means. Once again, think vanilla. BDSM is one that amuses me. Tickling very well is "a dom and a sub" situation. The catch, uninformed society. "Honey, I bought a pair of handcuffs!", "Oh! Look at us! So kinky!". Their knowledge starts and ends there. Have them presented with a hardcore piece of footage, and see the horror in their faces. Same with some hardcore tickling videos, those you swear the 'lee could die at any minute. At the end, it looks like they did. Weirdly enough, even the tame tickling pieces are seen with weirded out eyes. Some vanillas are "ok" with BDSM. Some have seen a little, others have seen more. In my experience "liking to get kinky" has a really good acceptance. The "tie down and lightly spanking" has never gotten me into an awkward situation, but when the "magical T word" comes into play...
It hurts to hear that "You are an effing weirdo". No matter how many times, or how thick-skinned you are. At that moment, you are not you anymore. You are not a person with feelings, a life, a past. You are "the creepy fetish guy/gal". It can ruin a person's life. If word gets out, you become the weirdo everywhere you go. The fear of telling it to someone who finds it creepy and decides to share such private piece of information with someone else could damage them in many ways. Social media is cruel. Mouth to mouth wording also spreads fast. What would your crush, your boss, your family think of you, if they knew? Why our likings have be "fetishes"? It is what it is. A liking; a kink. Unusual? Yes. Abnormal? No. To each their own. As long as done safely. "Fetishes do not exist", if we consider the usage of said word, they do not. As long as your liking is not your only source of pleasure, why does it have to be a "fetish"? Another problem comes to mind. Myself, and many others do not want to limit ourselves. Limit our choices. "I have a 'weird fetish', might as well try to find someone in a website/forum/app". I want to go out, and not have to "choose from a selected few". "These are people who accept my kink... which of them is sort of my type?". None of us should expect to be accepted by every single person out there, but when the majority is against you... tough, to say the least. Why "are" we abnormalities? Why "are" we the "creepy foot people", the "tickling weirdos", the "BDSM psychos"?
Ladies who may be reading this... what is wrong with vanilla women? A huge percentage loves shoes. They get pedicures every few days. Why in the, pardon the expression, hell do they hate feet? Hate having their feet touched or even looked at? Why tempt us? Not only the ladies, anyone reading this. A plausible answer would be very much appreciated (aside from "they are probably ticklish"). What those vanilla women do not seem to realise is that, most likely, men created these trends way back. Centuries ago, the dressing code was so strict, seeing a bare foot was exciting. I am using feet as an example, since it is a huge turn on to me. But in reality, any "non-conventional" body part liking is seen as abnormal. Enough trouble has been seen from expressing that I thought someone's feet was pretty, I cannot begin to imagine saying the same for armpits, for example. The female body is such a masterpiece, every single part can be erotic. Why the rejection of others? Cursed be the "breasts and bottoms" society.
Excuse the wall of text. I have not tickled anyone in over 4 years; as a 'ler, it is driving me insane. The subject itself, of acceptance of said "fetishes" is a touchy one. Pardon the venting. My comment is irrelevant and unnecessary; it won't change what has been for years. "Fetishes" shall remain as they are. Acceptance is a blinding illusion, speaking from a majoritary society standpoint. All we can do is hope to find that special someone in our lives, who understands and either "accepts" our kinks or, ideally, likes it and complements us.