Asking a silly question but...

I came across a mix online of classic disco tracks but they all had updated and modernized beats added to them along a house kind of sound. Are modern DJs taking all of the classic songs and updating them with a more techno-ish/house sounding beat to have them appeal to a younger audience? Is this a new trend? Sorry for my ignorance here gang, but its been at least 10 years since I've been a club so I have no idea what's being played.