Chuck: The simple reason and answer to your original question which I think you already know, is that it sells well.
That's what we do here in the good old US of A, we sell stuff.
Trap is the granddaddy of all the shotgun sports, being a featherless remnant of pigeon shooting adapted to the 'masses'.
We have masses here, and the tendency in this country is inclusion not exclusion in sports which the participants wish to grow (in order to sell more stuff).
Remington can be blamed for skeet, which was simply another way for them to sell their wares.
Wonko the Bane seems to think that if the family can play too it's not much of a game, but there's no arguing with the popularity of the sport and the register receipts.
You want something different, it's available.