Rudeness or honesty? Some people can't handle honesty, especially nowadays. If you have been in a few times and overloaded your bike, then you are the reason for the damage. BUT another bike shop owner might pat you on the back and say nothing, and soak you for repairs over and over and over. Now, who is the rude one?
Like I tell my patients, it would be a LOT easier to say NOTHING than it would be to tell you that you are doing wrong.