Your points are well taken except on the competetive thing.
I offer a hold on items for months until a customer can pick them up, a brick & mortar shop location where my customers feel very comfortable "hanging out" and talking with us, we have a bit of storage (free of charge) for two ofmy better customers. Keeping this in mind, if I then had to get into an all out price war with competetors on something like Britains, it would make it very hard for me to allow for all those extra perks of being one of my customers.
As soon as the dollar alone dictates the nature of a relationship, the relationship is lost and the business is now just that, business. I recently lost a customer due to this. He had a lot of perks and then began taking advantage of me, like it was his right to tell me what I should take back after having bought it over a year ago at a discounted price. When I had to revoke some of the perks he was getting it became strictly about the money on his side. My point was about the relationship and he lost that. He still comes back from time to time but it's not the same for him. And, to be honest, we are usually talking about no more than 5-15% on many items (Britains can be 40%) so the amount of money being saved isn't all that great.
These folks who wheel and deal at toy shows: Do they really get to know you on a personal level locally? Are they around for you to stop by and BS with you about the latest and greatest of the companies they collect? Are they able to notify you of the latest news from these companies? Are they really truly there to help you out or do special favors or put holds on items for extended periods of time? Are they really there for the dedicated collector? For the most part no. And they don't have the rent and overhead we shop keepers have. They have a few hundred bucks for a table, a hotel room and the cost of gas to deal with.
I suppose it's all relative. I am fine with people looking and seeking out better prices but if that is what our relationship is then don't expect much from me. I have a business to run and mouths to feed. For me to be good, kind and understanding towards a customer, I need the customer to be good, kind and understanding towards me. Also, discounts, storage, extended holds on items, special orders without payment upfront and all of the other things I offer have to be earned and developed just as you would develop and earn a friendship.