I'd expect that pop culture rides on the surface as something of an ideological superstructure. Maybe that's not mainstream culture's only role, contrary to Marxists, but it's a prominent one. Popular culture tells us what we want to hear, so it can't be too challenging to what we take for granted, including our profane preoccupations. Religions are like philosophy and the arts in that they have a higher, "spiritual" or existential calling. So there's that classic clash between sacred and profane messages.