1. It's nothing new to have pet store employees have no clue about reptile care. It's not exclusive to PetsMart and SOME PetsMarts do have good employees.
2. Talking to the employes and attempting some calm dialogue explaining that people NOW think that crickets are a unsuitable diet and that small rodents are better is a much better way of helping make change happen.
3. Buying anything from a store that doesn't care properly for the pets, doesn't relate good care advice or gives false info only supports that they should continue what they are doing. There's no incentive for a store to alter their advice if people are giving them money, no matter if they're telling new owners to feed their BPs apples.
4. Large tanks are not as bad for corns as for BPs. Corns naturally roam about searching for food items, while BPs are ambushers. I've started corns in fairly large tanks with no ill effects. As long as they have areas to hide in, and corn babies will "hide" underneath even just shavings, they've never seemed to have any issues with larger tanks.
5. Kaplan has done more to hurt reptiles kept as pets than PETA and HSUS. She pretends to be an authority that loves reptiles when she's setting people up to kill the pets and thus become disenchanted with keeping them at all.