I wear speedos everywhere...even to water parks. I've only really ever been called out once...by a 9 year old no less...when he, himself, was wearing jammers. He asked in that disgusted tone, "Why are you wearing SPEEDOS?". My response was, "because we're at a water park! You have to wear a swimsuti when you come here." Then he challenged me to a friendly race in the lazy river...of course he won...but that was it.
The only other mentions I've ever had were the lifeguards at that same park commenting that it was a Team USA suit and they were like, "Rock on!". During that race with the kid, I had lost my $700 Rx Oakelys, but wearing speedos made it easy for the lifeguard to identify me
Got those back by the end of the day.