The plural of vinyl

..is vinyls. Some idiots have got it into their head that the plural of vinyl is vinyl. You might like to think that this is all tongue-in-cheek, but in fact there are plenty of places on the Web where you can find examples of people peevishly telling off other people for saying "vinyls". Do these people also say "I bought five cheese" or "I bought five beer"? I doubt it very much. And if they do, that's idiotic too.