St. Louis has good manners, or some people want you to think so. I doubt that we are better or worse than other cities. Except maybe Japanese cities. The people there are amazingly polite.
The billboard on eastbound I 44 gets everyone's attention. There are a couple of others. One of them, also yellow on black, says "I 'Heart' STL". The third, white on red, simply says "LOVE." They were quite a mystery until it was revealed that the billboard company itself did it just as a pleasant gesture. Sure beats "this space available."
Not far away sits the Courtesy Diner. Imagine going in for coffee and a piece of pie, have the server bow, gesture toward a convenient seat and ask how s/he may serve you. No, I don't think so either.