I've noticed he wears a lot of skateboarding shirts, recently saw him in a Nike SB shirt and I've seen him in an Alien Workshop shirt as well as many other skate brands. I love skateboarding, grew up doing it just wouldn't peg it to be Dana's style. DFW jr. let us know! 
Most are given to him by friends from the shirts that I see at weigh ins.
The brands probably just give them to him.
I didn't read much into it so don't quote me on any of this but I believe his kids are really into skateboarding.
Dana has always been in some sort of tight bro shirt or skate shirt I've noticed before
Dana White the 45 year old 15 year old
cheesesteak - Dana White the 45 year old 15 year oldLol
Extra-Shmediums-R-Us
Dana White doesn't wear shirts, shirts wear Dana White.
If it ain't Dutch, it ain't much - Most are given to him by friends from the shirts that I see at weigh ins.This.. Rob Derdyck is a huge mma fan and is always at the fights. Him and Dana are pretty close. That would explain the Alien Workshop clothes. And Nike sponsors multiple UFC fighters. Doesn't seen like a stretch that Dana would probably have been able to procure some freebies there also.
His son is a huge skateboarding fan. hence the skatewear. Skateboard clothing has taken over the market its not just him. get with it UG!
Baby Gap
forget that and go to threadless.com
the fun never ends
from the egg shop, u goof
Dana looks cute in a T-shirt.
Korean zombie
The little kid's bin at the local record shop in the mall
SE555 -Lol
There was an interview a while ago where in he actually with a straight face claimed that he was "always part of the skateboard and surfing crowd" - rotflmao
You all know that if you had his money you'd wear whatever the fuck you wanted too. I remember Bill Gates back when I was younger. Rich as hell, never combed his hair.. 
I really doubt half the time he even knows what's on them.
Jeremy1983 - Baby Gap.