About regular clothing --
First of all, I'm not one of those eccentrics that wears suit coats all the time. In fact, I never wear one except on Easter Sunday and Christmas Day (to Mass). On normal Sundays, I wear a short-sleeved dress shirt (button-down) with a tie to Mass.
I also get most of my shirts cheap or free.
At home, I wear some T-shirt or other. I'll wear "logoed" T-shirts (which I got for free) if I'm working outside -- I want those shirts to get ruined first.
In short, I'm a very down-to-earth sort.
But since I stopped being a teenager, I've thought it ridiculous to pay $16 for a T-shirt just because it has a Nike logo on it. Or a large brand name written on it: Abercrombie, Tommy Hilfiger, etc. The big question: WHY? All those brand names emblazoned on the front of your shirt could POSSIBLY do for you is say:
A) I'm a sheep. Baaa! Just lead me and I'll follow.
B) I want to fit in -- badly. Somebody please love me!
C) I'm dashing, groovy, hip, radical, def, cool or whatever. Word!
D) I paid good money for the privilege of being a walking billboard to make this brand name even more popular.
None of those reasons are compelling for me, so I choose to shop at Sears, Kohl's or other stores that sell normal clothing without logos. Generally speaking, such clothing is cheaper.
As for vulgar slogans, that should be common sense. That's what worldly people wear. Aren't Catholics supposed to be "in the world, but not OF it"?
Matthew