saulsayscall:

I don’t know if I missed something, but why did Jimmy succeed in the interview and then turn it into a lecture about employment? Was he really trying to get a job? Was he just going around teaching a lesson to small business owners? Does he just want a job with a smarter boss?

Found here

According to Bob it was because the salesmen reminded him too much of his father due to their gullibility and he realized he could not respect them enough to want to work for them.