I'm a white guy who's almost 60, and I frequently get asked by AC staff if I'm SE, in the right line etc. Frankly, I don't care, and because I am always in the right line, I really don't understand why I should. I seriously wonder about the mindset of those who who are offended by this.
By asking, AC employees are trying to preserve priority resources for those who qualify. That benefits me, doesn't it?
It doesn't surprise me that they can't tell who qualifies just by looking. An expensive suit doesn't guarantee SE status.