With all due respect, the time to ask a guy if he wants to extend his time IS NOT when he is standing there with a hard on. The old saying "a hard dick has no conscience" always rings true.
He may not be as big of an ass hole as many are making him out to be, and you are certainly no clock watcher.
Sometimes it is best to leave a situation as best you can, he was a cad for taking your time with no compensation, but you could have taken the high ground and just let it slide, especially if he was due to be a repeat customer, who by all accounts, would not let this happen again.
The fact that he did finally make good is a plus, but a real Gentleman would have done that without, as you said, all of the extra haggling.
Just remember, even though this is the 'hobby', and the Ladies are strictly business, men tend to be really stupid when it comes to thinking while in the heat of passion.