Oh boy... I have an extensive history on dresscodes and issues with the way I dressed and I've been over this in another thread once. I should look up the link for that. But the short of it was; school wasn't happy about some of my choices of t-shirts (and prints thereof) and that resulted in a lot of issues up to where I made national media.
Further down the line I've been refused entrance to pubs and bars over appearance, which I guess one might attribute to dress, but I guess hairdo and a few other physical features might play part in it.
I've always found it quite petty to be bothered about dresscode. An argument I once had with a pubowner who refused to let me enter ended up in me telling him "I'm not sure if I would feel welcome in a pub of which the owner thinks the majority of the customers are a bunch of prejudiced bigots that judge people on the way they dress". Of course it didn't change his mind and I quickly left with my then girlfriend and her sister.
However, it is not to say that I don't like it if people dress "nice" or more fitting and I guess for someone who is somewhat connected to the goth scene and a few other more fringe subcultures, style and the way someone dresses does play part, however I've never considered someone to be more or less part of the subculture/community because he's showing up in a pair a jeans and tennisshoes instead of whatever people are wearing (assuming that jeans and tennisshoes are not the type of attire people wear there).
Because of the entire issues I had with clothing it does sometimes put me on edge when a friend asks me to come along for a few drinks in the weekend, since I have no clue what the policy is at the door. And often I can't find a policy, except "we have the right to refuse anyone" or even a bar here that says "appropriate attire required"... how's that for us aspies.. what's "appropriate"? If anything I don't feel like going to the bar first, ask the bouncer for a complete rundown, check out other guests which might be out for a bit of fresh air and copy from them when I already made a trip back home to get dressed.
As for attire for work; I rarely wear anything really outrageous I guess. Yes, I own a pair of platform boots, a pair of stylized "combat boots" with lots of metal detail on it, but I also own multiple pairs of sneakers. I usually wear black army pants, something that seems to be a problem already, but I just don't do jeans. I don't like to wear them, simple as that. And that's the closest thing, since I'm sure that showing up in sweatpants is a no-no as well.
After my run-ins with school and dresscodes, I've been a supporter of uniforms. Either uniforms in school or uniforms at work. It takes away a lot of ambiguity on what's ok and what's not. The downside of course is, creating a nice fitting and good looking uniform that suits everyone.