My earlier response is my experience with the seamier side of stocking, where the sport of fishing is reduced to the act of catching meat and fish size/growth is pushed to its limits. I have had satisfying days fishing for stocked trout. Even frustrating days when a net full of fish is thrown into the pool I'm fishing in and I can't get a bite for the life of me. The reality of fishing in an area with as dense a population as ours is that stocking may be needed in those locations that receive high fishing pressure. Looking at the factors beyond the different habitats, I have often wondered why a stocking program is required for trout, while none is for large or small mouth bass.
Managing the fishing pressure is the key to reducing the need for stocking. This may not be popular but closure of streams with viable, reproducing populations of trout during the spawning period might help the fish. After the anger of having streams closed by the MDC a couple of weeks ago subsided, this was my first thought on the effect of the closure. Since the streams are open again (Wachusett area), we won't find out how this would work.