You are going to tell your team, friends, and other users this story. Just by telling them about this a-hole customer is immediately going to bring the feature into the conversation. What if everyone you told snaps back with 'Well, he may be a dick, but thats a great feature' or 'That feature sure is stupid!'. This feature request just got more attention than any of your previous users requests.
The best feedback I get is from my asshole customers. They are vocal and upset. Something didn't go their way and they are unhappy. If I can fix that I get more happy customers.
Also, my polite customers are generally too happy/polite. Its hard to get feedback when they love your product. They'll put in pretty good feature requests and talking to them is always easy. It makes me feel really good when people love my product, but its really hard for them to tell you how much feature xyz sucks. Generally, we have to look at the logs to see what people are using/not using when it comes to happy/fanboy customers.
Of course, it is not ok to act like a dickhead. Being well respected is usually the best way to get things done.