Being somewhat of a cloud chaser I think that might contribute to the problem. I'm sure I wouldn't want another cloud chaser blowing it right next to me when I'm eating, but at the same time I would simply just wait to vape until I'm done, outside, and in my car.
I wouldn't mind a tootler so much - just because of the low amount of vapor being produced, but there isn't really a way to differentiate the two without discriminating when it comes to creating laws or rules.
Best rule of thumb is to just ask the manager "hey, is it okay if I vape here?", if yes, blow little clouds, not huge ones, and sit away from other customers. If no, don't do it at all, or just wait until you're outside/in your car. It's called being courteous.