Kind of a silly question about the community lots.

Yes, they will. You will see NPCs planting in community gardens, so if you want to grow something there, be quick about it.

Community spaces function as intended. However, make sure to remove those garbage dumps in other versions as otherwise sims will keep dumpster diving there.
Also, stalls will open on all versions, so if you want a community garden with a produce stall, go ahead. No need to hire a vendor.