Excellent point! 

One evening I was heading out to play darts and the only jeans I had were ones I haven’t worn for several years.  Turns out that since I last wore them they shrunk (there could be another explanations, but we won’t discuss it).  Anyway, the end result was that the jeans were a bit snug to say the least.  Much to my suprise, I had several beers bought for me at darts that night.  Apparently, tight jeans = free beer.  The fact that it was gay men buying the beer made it no less flattering.  As my wife remarked "Hey, gay men would know a good butt when they saw one."

Also, kudos to you for outstanding use of parenthetical asides  

My pants have had the same problem in recent years, I find. Perhaps we are using the wrong laundry detergent. How interesting that they don’t get shorter in the leg, only in the waist.