Quite the over-simplification, though. The story has an important additional twist: the guy was sold on the idea by Tesla because 60D was going away, Tesla's timing/pressure being presumably to make sure Q2 delivery can be made. Then that very same Tesla (after all, all the sales people are Tesla), changes the pricing so that the customer that was told there was a hurry, actually could have gotten more by waiting. Customer contacts Tesla asking to fix this, Tesla easily can fix it all (a click on the computer really), but demand 500 dollars to get it done...
Given the pressure from Tesla to close the initial sale, and that it was Tesla that then afterwards changed the pricing in a way the customer could not anticipate given the rush, and Tesla can without unreasonable trouble still fix this, asking to waive that 500 hardly seems unreasonable.
This is why places like Amazon.com do pricing guarantees and all sorts of stuff. It is just good business to keep customers happy, especially when it can be done reasonably. Some policy to guarantee customer pre-delivery pricing decreases, without change fees, would actually just be good policy. After all, Tesla does know when prices change, but the customer does not. So the party having the upper hand giving a guarantee to the party without is, well, fair and wise.