I don't mean this as a dig, honestly I don't, but if you're walking around life getting offended by things as small as that you should probably re-evaluate some things. Getting offended by something, at its root, is just a way to make people feel bad. Either just you (if the person meant to offend you) or you and the other person (if they didn't). Either way, it causes nothing but pain.

That's ok because it's an emotion with purpose in that it drives you to act. I am offended by the conditions in many African countries so I donate to those charities. I am offended by the jokes that person is telling so I don't hang around them anymore.

But if you are getting offended at something like this, where no action can fix it, than you're just causing yourself undue pain.