I can understand the logic though of a fixed tip. There are all kinds of situations where a server spends the same amount of time/effort for each table and get different tips based on what the person ate?
Why does that make sense that I would tip more because I got a steak instead of a burger and the server had to just bring it to me in either case?
I guess I tend to eat at the same 3 restaurants around my house. They all know me and are also my neighbors. The social pressure to not be "that guy" has pushed me to tip generously I guess.
There are people out there that honestly think this is normal behavior. Hey your experience was terrible, but have this $5 your don't deserve.
I live in the US and only tip when service is good.
The default assumption is that customers will tip at least a reasonable amount for all service. If you aren't going to do that you need to announce your intentions in advance. Whenever you go to a restaurant just let the hostess know your plans. That way you won't be deceiving people who are serving you.
Regardless, I don't go to restaurants because of this.
Or realize how stupid that sounds
Your intentions, on the other hand, are very unusual and not standard. That's why it's important for you to tell people what is going on so that they are not caught by surprise.