Janna:

The price is, you become (if you weren't already) close-minded and therefore uninteresting. You can never have a polite conversation with someone who disagrees with you because you wind up questioning their motives instead of examining their arguments. People react badly to ad hominem attacks and things degenerate to name calling. Happens here all the time.

To be fair, this is a problem for lots of folks across the political spectrum, but it does somehow seem more grating from liberals because in other contexts they're always going on about open-mindedness.