I don't know how many others do too, but I think that's some pretty bloomer shit to be able to believe you'll be around for communism. What can it hurt to believe we're closer to it than we think?
I mean if folks don't believe it's going to happen, they might not feel like putting in extra work. But if it's around the corner, we can do little steps in our lives to make things better faster.
From each according to their ability, to each according to their need. I'd imagine very quickly a small community could support a member who wouldn't contribute at all. And I doubt anyone would really fall into the "contributes nothing" territory. Takes all sorts of skills to build and enrich a community, physical labor is a small part.