Technically it's copyright violation even if you aren't making money from it. I think the website deleting it is really just them trying to protect themselves from any liability more so than they are trying to punish you.
I cam across a music profile on MySpace once in which the artist/band claimed to have written the posted songs. They were blatantly obvious (to me at least) as Portishead samples... which weren't even much different from the original Portishead songs they were sampled from. It basically sounded like someone had sampled their songs, then used those samples to make the songs again... without any credit to the original band.
I used to do a lot of sampling in the past, but I backed off since the whole micro-management of copyrights began around the birth of Napster. I began to focus on software synths instead. You can create some cool sounds, especially in Reason, without messing with sampled loops or whatnot. It's actually not hard to get proper rights to use stuff like that though. Look up the Harry Fox Agency. I'm not sure if it applies overseas, but it's still worth a look.