^I know exactly what you mean. I guess in the past 2-3 years (the time I've heavily DL mixtapes), I've just gotten use to the fact that mixtapes are for the hardcore rap/HH fans, and studio albums are for record companies and general public.
I think it's also that way just cause the mixtape scene has largely gotten away from the older/original style of mixtapes where you're rapping over popular/radio tracks, and are basically making free albums. I'm sure you probably notice when a tape comes out (depending on who it is), if it has mostly known beats, a lot of people (recently) tend to frown on it. I don't mind it, cause those are the type of tapes i grew up listening to anyway.