I imagine it wouldn’t be profitable at all, but I would love services like flights, resturants, movies, etc that were adult only. Would be nice to just not have to deal with it.
It’s unavoidable and a part of life you just have to deal with though. You roll your eyes, you turn up the noise cancelling on your headphones and you deal with it. But at the same time, parents should do all they can to keep their kids quiet and well behaved and maybe consider whether flights before their child is even a toddler are the best idea.