Actual reasons haven't been mentioned. What's been mentioned is the law's customary practice of distinguishing between economic activities it labels "businesses" and those it doesn't, the law's customary practice of distinguishing between economic activities it requires licenses for and those it doesn't, and the law's customary practice of distinguishing between the participants in an exchange based on which one is defined as "customer" and which as "seller". All these amount to saying we don't prohibit johns from discriminating because we categorize them as members of a class we don't impose anti-discrimination laws on. That doesn't actually qualify as a reason.No, they're entirely separate issues for all the reasons mentioned.
I'm not following you here. It's the difference between a personal transaction and a business transaction. Where you choose to spend your own money is a personal transaction for you and it's not the government's business. When you sell a product or service, it's a business transaction and it's the government's business. It's like if a McDonalds' franchise doesn't want to sell to Jews, that's a problem that the government has a role to intrude upon but if a guy doesn't want to eat at a particular McDonalds because it's run by Jews, then he's a racist dick but he's not doing anything illegal that the government should get involved in.
This raises a natural follow-up question. Suppose a licensed Certified Public Accountant quits his tax preparation job and goes looking for a new job, right after the owner of the tax preparation agency he works for retires and sells his company. This raises eyebrows. The new owner reads the agency's file copy of the CPA's resume; she does some fast checking of the guy's previous employers; and she figures out the guy has always worked only for black-owned businesses and he quit because she's Asian. Should the terms of a CPA license require one to sell accounting services to people of all races on a nondiscriminatory basis? If the new owner reports him for racially discriminating against her, should his CPA license be revoked? Should the licensing officials warn him that he'd better take a job at a non-black-owned business or lose his license? They wouldn't be forcing him to work for non-black people, after all, and making a living as a licensed accountant isn't a right.
If it can be proven that he's violating non-discrimination laws then he should lose his licence the same way that he should lose it if it's proven that he's engaging in any other kind of illegal activity.