This sort of snobbery (don't mean to be insulting here, but that word is the best I could think of to describe it) is exactly the problem at hand. You say that there's nothing wrong with enjoying Pokemon for example, but follow it up by saying that you'd be worried about people who didn't enjoy natural history, philosophy or Shakespeare. You take it for granted that there is something inherently superior about those things that isn't present in (say) Pokemon or Call of Duty, but there simply isn't, it's all 100% subjective.
When Shakespeare was alive his "modern" plays were considered to be the lesser, more disreputable entertainment for the masses, unlike the more high-brow Latin or Greek plays. The fact is that people will always find reasons to look down on other people, and that's all it comes down to. An interest in philosophy is no different, no better, and no more useful than an interest in digital soldiers shooting each other for points. Nor does it have anything to do with a person's intelligence.
My opinion is that people should enjoy literally anything they want, so long as it harms nobody, and they shouldn't be judged for it. Sadly, many people find it difficult to accept interests they don't understand.