They're not losing a lot of business by not doing an out of state transfer. That is your opinion. Most shops LOSE money by soaking up time doing transfers on guns they didn't sell.
If they don't want to do it, they don't want to do it.
I don't know that they actually lose money by doing a transfer.
Lets say that an employee is making state minimum, $8/hr (they likely make more, work off commission, etc. but for the sake of this example, they make $8)
You want to do an OOS transfer and based on a post from earlier in this thread, they said it would be $50.
You buy a gun from wherever that is out of state and want to have ZHA do the transfer. At this point, ZHA has lost no money. They can't sell what they don't have in stock or what they won't price reasonably (or negotiate price) and that is probably the reason that you bought it from someone out of state anyways.
Do they lose potential revenue because of those factors? Sure. However, for an employee to do the transfer work, I don't think the shop loses money (unless there is some fee the shop pays the state for that privilege that I don't know about). If anything, they make a little bit for their time and efforts. In fact, by my estimate they would be making $46 on the deal. This is assuming the transfer process takes no longer than 30 minutes and assuming the employee is paid the state minimum.
Is it inconvenient for the shop? Probably.
Is it this stores right to set a price and/or flat out refuse to do something they don't want to do? Sure is.
If you don't like it, there are PLENTY of other shops that will do the transfer, and probably be grateful to do it in order earn your business in the future.