Scruffy,
Don't these guys know not to start anything they have no intention of finishing? Initiate something with a guy and then not finish him off? For me that'd be like going to the Cheesecake Factory and passing up dessert.
If I initiate the cruising, I feel I owe it to the other guy to at least make the attempt to finish him off. Only if he decides enough is enough do I break off. Sometimes, it means I shoot before he does. And sometimes, him getting to see me shoot sends him over.
I've been in the situation where the cruising takes longer than the action many times. There's this one guy that likes hooking up with me when I see him. But he won't hook up with me for at least a half hour after he's arrived. He will stand around forever. Then he reaches "simmer" and he's in a booth with me.
But since cruising etiquette isn't required learning at the better finishing schools any more, guys pretty much do what they want. They cruise until sated then run. I guess they figure their actions have no future consequences. Eventually diminishing returns weed them out. After a while, when they can't catch anyone's eye, they'll get the message. Or maybe not.