"Play" as a concept, is a clear social construct. The behaviors we call "play" is very obviously an innate instinctual behavior for humans, and is entirely plausible the same for bees. I see little here to suggest that this implies sentience apart from simple anthropomorphism.
At least I can't imagine any sort of logical pattern where this improves fitness other than because it is emotionally gratifying, which I would posit necessarily intersects with biology beyond the very simplistic instinctual-automaton model.