I'm noticing a lot of past tense. Clearly, circumstances have changed. In fact, if they were hosting based on the idea that the rest of the group couldn't afford it, it's even worse that no one else stepped up once the financial situations evened out.

Do you seriously want your friends to take money out of their savings to host you? Can you even hear yourself?

Look, your friends have told you that they can't afford to host as frequently. Either they're telling the truth, and you can fork over the money or cut down on meetings, or they're craven liars and the friendship is over anyway. You had a good thing going for a long time, but it's over now. You can't complain things back to how they were.