My club is completely overrun with high school kids getting in their team league skeet, trap and sporting clays shooting. It is the best thing that has happened to shooting, in my part of the world, in my lifetime, and I see a lot of squads full of pretty high school girls, something that was unthinkable when I was that age.
I see a few autoloaders. But, I see way more low end pumps, the majority with black plastic furnature. I quit counting when I got to 100 one day last fall. I would guess the coaches suggest they start with something simple, cheap, and durable, and move up later, if they want to stick with the sport. I'm almost always the lone SXS guy there. Of course, the only sliding breech guns I ever seen there are mine, or, my friend Bills, when he makes it out.
Never seen a SXS shoot at Metro Gun Club. I'll suggest it, when I renew my membership next week. I've also never seen a kid on a school league, at my club, with a SXS double of any type. That kid might be out there, I just haven't met him/her.
I don't usually shop at Cabelas, Larry. I have three locally, but, I suspect that 10 units of Dickinson guns represents a big part of the inventory for SXS guns, for all the stores, for a year. Yes, the row of Franchi, or, whoevers, O/Us I saw at Gander (I didn't handle any of them) was mostly 20s, but, I think there were a dozen plus. Doing the math, it seems that sales are concentrated outside the SXS design at the retail level.
A sample of 300 grouse hunters across the US would seem like a really small sample, Larry. Hell, I'm not a member, I'd guess Lloyd and his FIL and his lovely wife aren't either. Comparing 300 reports to just 50% of the number of small game licenses sold, in just the state of MN, would render that number completely, statistically, irrelevant. I'll save you the trouble of looking, Larry-there were 302,974 small game licenses sold in MN in 2011, the last year that is completely compiled.
As to your comment about Ithaca, or whoever, selling thousands of guns they brought in, I think a simple truth is fewer shotguns, by far, are sold now than in the era of the Pepsi Generation, and they have to be offered in configurations that will allow for the most unit sales. Each sale today represents a lot more effort on the manufacturers and distributers part, and the advancement of manufacturing techniques in lower cost countries, like Turkey, has a lot to do with the variety that we do see. I suppose the people bringing in those guns have better sales targeting and demographic information to go on, something an importer bringing in Spanish guns circa 1972 could only have dreamed about. I doubt the sellers wanted to be stuck with a bunch of 16 gauge imports back then.
That said, I still wonder about all those O/Us in the rack I saw at Gander. Somebody is buying them. Not me, but, somebody.

Best,
Ted