In my experience, pet stores sell their stock for way more than any breeder I've seen. You get what you pay for when you buy from a breeder (most of the time) and that $300 price tag is usually for an especially valuable animal with a traceable lineage. A normal dragon from a local breeder is often $20 or less and you can vouch for the fact that it hasn't been shipped around, exposed to disease and environmental stress, nor has it been housed in huge quantities in an "every man for himself" feeding situation.
Petco and Petsmart do have nice animals on occasion, but they are not high end morphs and thus do not cost $300. All of my dragons came from top notch breeders and I gladly paid several hundred dollars each for the quality (Angie Husk, Carolina Designer Dragons, Kevin Dunne, Georgia Bearded Dragons, etc). When I breed my extremely high end dragons, I sell my Red, Citrus and Leucistic hatchlings for less than half of what Petco/Petsmart/Petland charges for "Fancy Color" bearded dragons. Even with shipping, you pay less for my dragons than you do at Petco in most cases.
For your next dragon, look for hobby breeders with high end stock to get the best deals. I have no name in the industry and I cannot command high prices, yet my animals only came from the best in the business.
I am glad that you are happy with Dudley and the customer service of Petco, but I still enthusiastically signed that petition!
PS... I have worked at Petsmart and my friend and former roommate currently works at Petco... both stores purchase reptiles from USGE and Sun Pet. Neither will purchase animals from "local breeders" because they have large contracts for wholesale pricing on mass produced animals from these two large facilities. So yes, Dudley might have been captive bred, but he was certainly not hatched in a warm and loving environment.