They do help socially unless you plan on only socializing with Engineers. You are going to meet people from other fields and some of them will probably know a little something about literature, art, etc. Who knows, you might like it, and it may be a good conversation spark.
Speaking for myself, I went to Brooklyn Polytech University and there was a requirement for Humanities classes each semester to complement your concentration classes. You know what? I actually enjoyed those classes for a few reasons. It gave me insight and actually interested me, and it actually gave my mind a little bit of time to unwind, not to say Humanities classes are bullshit or anything, but there is a different gear shift going from Computer and Electrical Engineering classes to something like Art History. I would say being well rounded in things you aren't really majoring in does help you in the real world, especially if it is something like history or the arts.