Negotiation? What negotiation room is there with a monopolistic distribution system?

No one but noob walk ins pay those retail prices quoted in the US.

Stern distros in the US are more of an oligopoly who actually have to compete for your dollar to get a sale. Stern try to regulate that by sending out memoranda to their distributors immediately prior to product shipment which contain what is called M.A.P (minimum advertised pricing). This is not binding (as like Australia, that is illegal) but it is highly "persuasive" when you belong to a limited supply chain like pinball machines. That is why so many "under the table" deals occur with US Stern distributors to customers. I imported my BIBLE in this manner and it still came in way under what the Aus distro was charging NIB at the time. The downside is that there is no warranty whatsoever and the local Aus distributor doesn't want to know you.

When all is said and done, it really all comes down to how much value you place on a limited warranty and local after sales service (if any). Because that is all the added value you are getting by buying locally.