Indiana Beach has a spot like this that you feed them popcorn! I remember as a little kid going over there and you could sit there all day long. It was really cool. I have not been over there in many years so not sure if they still have it but I do know that everyone enjoyed it so I am sure that they still have it. There is a guy who sells popcorn right there by this spot.
I worked at the Al Faw palace in Baghdad in 05 and 06 - there was a bridge to the palace and there were these carp like fish that folks you used to feed with bread and other crap from the chow hall... Not that thick, but it was pretty impressive. Folks used to fish for them. There was another spot in south Florida at a restaurant called the Two Georges in downtown Boyton Beach where I am from that had cat fish that thick from all the diners tossing bread into the water...it was creepy.