How the Christian engages culture and particularly pop culture are interesting questions. There are two bad answers: “We can avoid sinful influences by simply avoiding it or condemning it” and “I can do anything I please”
The former thinks of sin as contamination (usually); but sin starts in our hearts before it exists in something discrete and external that can be “consumed”
The latter is willful and ignorant, and not freedom at all: it is bondage to self will and to what others may think of us for consuming, or not consuming, a particular aspect of culture. We DO have the power to choose, but the people that talk about choice all the time are nearly always those that are bound by sin. There really is NO freedom except in Christ. Non-believers have widely varying degrees of overt sinfulness, obviously, but none of them, not even one, is free at all.
(Pop culture is merely a large, and obvious, part of the overall culture: business, ideas, politics. When one shops, one is either cheap, or indulgent, or occasionally thoughtful and purposeful, but you are always engaging the culture.)
While the “don't go to movies” crowd is right that much of what depicted is sinful, it can't be avoided simply by staying home. The other extreme is right in the sense that it may be OK to attend, but is often naïve about how much they are influenced by something simply because it is well done, or because it contains one good idea. Avatar, for example, contained the idea that systemic evil should be resisted, but it also promoted pantheism in a big way that was doubtless overlooked by a lot of admirers.
Our pastor had a whole series on engaging pop culture a few years ago: sports one week; I should look up the other topics. He and his wife are huge movie fans, but they are conscious about their Christian worldview.