I agree with you that some of this comes from snobbery and ignorance, but I think it's also motivated by a naive form of human curiosity. There's a line in East of Eden about one of the main characters (Samuel Hamilton) that talks about how he abhorred the sprawl of knowledge and increasing specialization of the human race. That trend has of course led to an immense improvement in the quality of life of our species, but I think it is a really disconcerting and slightly sad feeling as a curious person to realize there are huge realms of knowledge and skill that I will never live long enough to explore and enjoy.