I disagree.
The store is in business to sell me something. If they aren't successful it's not my fault.
I buy a lot of stuff from GP Bikes, less from Royal and others, because at times I get okay-to-good service and the price is reasonable. On my boots, they were cheaper than from my usual online stores. But, if I can save $300 on a $400 jacket, I'm not going to feel morally obliged to do pay the higher price because I walked into the store and tried it on no differently than if it was on sale next door.
Let's take that scenario for a second: If I walk into GP and try on a jacket and eventually chat with a staffer for a couple of minutes, then find out the same jacket is on sale next door at Royal. Should I not buy the jacket on sale at Royal for half the price? Would that not be "morally wrong"?
You can charge more for your product than a competitor and still sell your stuff. But you have to offer more such as inventory, timeliness, knowlegable advice, etc. That's where I see the local shops failing.