Not so much a 'rl' thing since it annoys me on Facebook but still.
People who can't get past the idea everyone doesn't like the same things, or that if they didn't enjoy a popular thing it doesn't make them special.
There are so many posts lately from people about Star Wars throwing words like 'sheep' and 'commercialism' around. One particularly special one was bemoaning all the posts the movie is getting versus 'more important issues', which sounds a lot like '... such as stuff I care about'.
Get over yourselves, folks.