I've read their approach to the situation. I find it a bit puzzling, but I'm not a shop owner so I'm not going to say what's best for them.
But I know the vendors that get my repeat business are the ones that make it the easiest on me. For me that means competitive prices, a strong web presence with clear pictures with detailed information of all their stock, easy transactions, and what I consider fair shipping and proper packaging.
Some of the "bigger" vendors have their issues too. There's sponsors that don't have gift certificate or paypal options along with other various issues.
I've dealt with the Boswells once via the store and once via ebay with Rachel. Great folks. I just find this debit card issue to be another minus in the things I look for in a vendor.