I may be impatient at a restaurant waiting for food, especially if I had been expecting it sooner. However, in general, I think I am a very patient person and not demanding; I generally have low/minimal expectations with people.
I do not eat at restaurants often, but I have had incredibly long service (more than an hour) once when dining out with a friend. We complained to the manager and he gave us a gift card. Other than that, I have had long "fast food" service, in which my friends and I have waited at least 20 minutes for one order. I became impatient at that time.
On the topic of impatience and Asperger's Syndrome, I do not think it can be decided just based on food and dining out. If anything, I might guess that patience is an AS trait. At least, I think I am incredibly more patient with people than they are with me, probably due to my low processing speed.
I work at a restaurant and people become impatient if they have to wait more than 15 minutes for their food.
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