Yea gonna disagree there. A company shouldn't have the right to end employment over inconsequential differences. That is not their authority.
So long as the individual is doing the job, which is simply to drive a bus in this case, everything else is irrelevant and companies should go get fucked for trying to dictate that. How he dresses has nothing to do with his ability to drive a bus and shouldn't be allowed to be a factor in determining his employment.
The entire point is he shouldn't have had to face any consequences for something so benign.