I dropped out of art school and had just about every hair color at one time or another. If you have an unnatural hair color, you may have to go a lot further to prove your professionalism. People with different hair colors seem to work in low-level, but hip, service industry jobs, or creative/ skilled jobs where appearance doesn’t matter (graphic designer, mechanic, tattoo artist.) The key in the second part is that your unique skillset outweighs your appearance. If you’re one of 50 people applying for a receptionist job, there are a lot of other people with the exact same skills. The employer doesn’t know you that well, and they have no reason to choose you over someone with the exact same skills and a more traditionally professional look.
It’s a lot like applying for jobs without a degree (something I’m also familiar with.) All other things being equal, the employer would probably choose someone with a degree. In order to beat that person for a job, I might have to write a more compelling cover letter, interview better, or learn more about their company. This isn’t unfair to me and I don’t deserve special protections for it. From the employer’s standpoint, someone with a degree is a safer bet, because it shows they have some background knowledge and complete something. It is my personal responsibility to prove otherwise.