Lots of sightings since I became an official DL, circa 2000. A few of the better ones:
1) A Chinese family at a grocery store: mom, teen brother, teen sister, and roughly 8-year old boy. The boy's t-shirt barely came to his waist and I noticed the white of his diaper, rising above the stretch waistband on his jeans.
2) A 30-ish couple at JCPenny. The man had an average build, but his diaper area ballooned in all directions. He certainly should have been able to afford disposables, so assume it was a cloth/plastic pants dare. Was in a hurry or would have lingered.
3) A thin, 60-ish man in a t-shirt and sleep pants at a grocery store. Again, his diaper area was totally mushroomed, so it must have been cloth.
4) An elderly couple entering another grocery store. It was early summer, but the man was dressed in a thick sweater, which had ridden up his back, revealing at least an inch of his Depends taped brief.
5) Not a good sighting, but an amusing one. A family at another grocery store with a 3-4 year old boy, who was tugging furiously at the waistband on his pull-up. He must have been soaked!