Just to clarify, it's "SNAQWELLS", not "SNAGWELLS". It's a Q, not a G. Not that it's a big deal, but it's generally easier to get my attention if you call me by the correct name.
Now, once again, I'm not saying that how you dress affects your ability to perform your job.
Let's go back to the business model. You're correct that many people who dress alternatively (to include unnaturally dyed hair, excessive metal potruding from the face, etc.) get hired and do their jobs very well. However, people who dress that way don't generally get promoted in the business world. When there are multiple applicants for a job, you need to stand out positively, and first impressions are key. It's a lot like that resume. If your resume looks like crap, or is filled with typos, it goes in the trash and you don't even get a phone call. If your clothes look like crap, you're not getting that second interview. Are there exceptions? Sure, but they've all graduated top of their class at MIT. That's a select few.
Officiating isn't any different. If you just want to go out and officiate sub-varsity games, and do the best you can do, it won't matter what kind of pants you wear or whether your shoes are shined. If, however, you want to do varsity, college, or higher, those things will matter; because you need to show more than rules knowledge to those who will make or break your career.
Is it fair to be judged by appearance? I think it is, to a degree. It displays one's willingness to do what it takes to get the job done.