Plecos aren't native to the USA.
The Hogchokers are called hogchokers because back during the time when almost everyone farmed, they took water from the rivers to water crops, etc and these guys would sometimes clog the pipes. They'd take them out and put them into the slop to feed the pigs. But sometimes the pigs choked on the larger ones so thats how they got the name Hogchoker.
You did the right thing putting them in a sand bottom tank. They need that. They eat worms that fall/burrow into the sand (live blackworms are best)