I got to see people buying teen or adult diapers only 4 times in my life.
Once in Asda, a family of four staring at the drynites packs for one of their kids (I suppose, the 10-ish year old girl didn't seem to be bothered at all while the 7-8 year old boy was all blushing).
More recently, not far from Clapham Junction a lady in her 40s was walking down the street with a pack of Lille adult nappies.
Many stores now display as many drynites packs as the other baby sizes, they must be selling a lot of them (well, at least that'd seem logical to me, they wouldn't stock that many of them otherwise). How come I have seen thousands of people buying baby nappies, and it happened to me only once to see a family buying drynites for their kids?