US customs

I am on my way to Seattle. I have a nexus card to be able to cross the border without a lot of hassle. You have to pay, you go for an interview you get approved and off you go. It is supposed to go that way. Today though I had a guy just nasty. He asked me why I had one. I am not a Canadian citizen and so the process if just a bit different but after all they approved me. He even went as far as turning around and telling an other agent how ridiculous is was that I had been approved. Boy, I have teeth marks in my tongue from telling him where to go. Going to jail though was just not worth my while.... What a jerk!!