I was watching a recent episode of DL TV today and they read a viewer email about Patrick dressing like a gas station attendant. He commented that he has two shirts like that and he said that apparently wore them too often. I had noticed the shirts as well, but to me this was like Patrick's trademark. It is not unheard of to have personalities have clothing they always wear during appearances.
The other point that was attempted in the viewer email was that it was making geeks look bad by him dressing down. Are we geeks really known for our fashion sense?
I have a few friends like Patrick, who are into tech, but also know their way around an engine. I find that it enhances their abilities when working on computer hardware. Someone thinking that looking like a grease monkey invalidates any opinions one has about technology is short sited.