A really gross question about a mexican way?

Ok Im sorry that this question is a little vile but I am stumped!!! My fiance works with a lot of Mexicans, and he says that when they poo, instead of flushing the toilet paper down the toilet, that they just throw it on the floor or in the garbage?!?! Is this true???? Isnt that unsanitary, wouldnt the smell be horendous? He says that he has also seen alot of this going on in public restrooms! Whats the deal?! Im not trying to be rude in any way, Im just curious as to whyyyyy? Thanks!