Being from Australia, where tipping is not expected or common, I could easily have been the ignorant type to tipping. But I did arrive in America knowing enough that tipping was a part of the culture.
What I failed to do on my first visit though was to take the time and research how much to tip. I do feel bad that there is a good chance some of those first meals I had while travelling might have been under a reasonable amount. But there might have been some that were over 20% as well.
thankfully I soon made some friends while travelling and did learn some best practices.