I'm with you, I don't understand what emotion people have when they say they are "offended". Especially when they are being "offended" on behalf of others.
I am not sure but I think I mostly intepret it as "hurting my morals or sensibilities". So none of the above.
but why are people offended by things they don't even consume? I suppose some people actually think "offensive" song lyrics (or video games, movies, books, etc) lead to more "depravity" or whatever, but nobody who claims to believe in science should be allowed to use that excuse without ridicule.