sorry you had this experience. I would expect payment for the time agreed. If he wants shorter, so be it.
If he's a regular, then if you feel like knocking back the $$ - your choice.
Sometimes, as said, its a matter of not getting what you want when the door opens. Not in this case - as he is a repeat w/you and I find your pictures spot on.
Sometimes, things come up in RL - and he still wants the date but can't make the whole time.
Still, if you buy a pie and eat half - they won't take the other half back...
To me, when you book an appointment - that time is SOLD - don't sell my time for a higher price and expect me to be happy, and I shouldn't expect to request less time when I get there... and expect you to be happy.