Anecdotal but where I go to school (a top university) people often will drink then take adderall since it focuses you while you're drunk so you don't seem as drunk but can still have fun.

I highly doubt however that it's more popular then molly and I know it isn't as popular as weed, which is still the recreational drug of choice. This might be skewed as coming from a good university hard drugs aren't as popular as some other schools, but I think it's enough to debunk a baseless claim.