+1

I like shirts that have designs on them, but messages? I gave that up in my early 20's. If somebody's opinion is going to change based on a cute slogan, it's not likely to stay changed.

Each of us are our own personal advertising agency, selling one product: Ourselves. How we physically present ourselves is 90% of our ad campaign because it reaches everybody we interact with; how we act, speak, behave, etc. reaches a tiny fraction of the world around us, and only those people who have either decided to tentatively accept us based on how we look, or who are forced by circumstance to spend time with us.

In short, if you dress like a jerk with an attitude problem, then don't be surprised when people treat you like a jerk with an attitude problem.