Maybe scheduling the first meetings could let people get used to get there and create, with some time, a base of regular users.
But if there are economic problems behind the choice to keep the chat, it's a different matter. It's a pity anyway :-(
Some times ago there were free chat room services, I don't know if they still exist, but TT could use that instead of a paid service. Or TT users could get used to meet somewhere else, like a dedicated IRC channel.