mine sleeps and hangs around my koralia as well. although he now seems to be hanging out in some mushrooms more often and mostly just sleeps by the koralia now.
clowns in nature are basically never found without a host, so when they don't have an anemone or something similar they will make due with whatever they find... it may look silly but it's just how they are!
Surprisingly, I have had multiple different types of clowns, and I have never had 1 host anything., I have given them different swaying corals, BTA's, long tenacles nem's, and bubble, the false or true percs never even noticed. The tomato's at least looked at my gifts to them, but then that was it. The clowns seem to just swim at the top of tank near the front glass.
I like the clowns, but I honestly think they are the dumbest fish I have had. I can put a net in my tank and the clowns would swim into it.