Ah, stories about the "good old days", back when I worked retail...and people wonder why I hate dealing with customers directly.
You always get your share of morons, hostiles, and crazies. Most either want attention and/or power in the situation, and as the "messenger" you take all of the abuse. You did the right thing by walking away and not "stooping" to his level.
Of course, when I worked in a convenience store right across from a university (in my early 20s much less, when I had a VERY short fuse), I pretty much went down to their level at the drop of a hat. Of course, job longevity then becomes a problem, but it helped that I was a strong enough worker in other areas to more than make up for my "lack of customer service skills".
