I hate them too but because they are expensive, ugly and do NOT work! Our local pool has now been closed twice since Memorial Day due to a kid who had on a disposable swim diaper that leaked poop into the pool. Disgusting and a massive inconvenience for all the families who had to hang for over an hour for the pool to be disinfected.
Our pool has, finally, switched over to reusable swim diapers. They work! They have wonderful leg gussets that form a tight seal and keep the poop in! While they cost about $12-$15, they are much cheaper than buying disposables in the long run. Within one month of the summer, you have made your money back. Imse Vimse makes some cute ones.
http://www.cottontailbaby.com/item_55/Imse-Vimse-Swim-Diaper.htm
I am thrilled that pretty much all the pools around here now mandate reusable swim diapers. I think it will be better for everyone in the long run.
Good luck finding an alternative!