The fact remains that prior to the baby betta craze, the betta available in most pet stores were actually edging toward 'old'. I agree that selling the young ones who are still on fry food is completely unethical and it is a good move to tell the management if the pellets being given are too big to be consumed (without soaking and pulverizing them, at least!) but the actual concept of baby bettas isn't a huge issue if the 'young, but not TOO young' criteria is being observed.
On the upside, the baby betta aren't selling as well as their new Halfmoon, Double tail, and Crowntail stock (at my local store, anyway), so I am hoping the inventory counts on this are the final word and they are more inclined to stock the more popular, older fish when the young ones die or won't sell. One can hope, anyway!