Indeed. I think that if a person cannot participate in modern society without being a customer with only a few competitors to choose from, then such businesses should have a "universal service obligation" and not be allowed to refuse service without a good reason. Such a reason should be mediated by the legal system.
For example a major chain convenience store with few similar competitors could ban someone for shoplifting, but someone innocent caught by this should be able to sue and win if the store cannot convince a court that such an event actually occurred. A mom-and-pop store wouldn't be within scope of this.
Suing isn't as useful as you'd expect. It costs $10,000's and months to even get to court.
Criminal liability for improper bans, and allowing citizens to directly charge the company with the crime (some states do this) would probably be more practical.
Alternatively, some variant of streamlined court (similar to small-claims court) could be established, where you could automatically use the court if the defendant had already been sued more than 10 times in the last decade for the last thing. The court would provide some sort of legal or financial resources to allow the customers to quickly sue without paying out of pocket, or spending much of their own time.
This could be solved with something like CFPB, but with the Chevron Deference repealed, courts are pretty much the only remedy now for anything until congress decides to write much more specific and in-depth laws.
For example a major chain convenience store with few similar competitors could ban someone for shoplifting, but someone innocent caught by this should be able to sue and win if the store cannot convince a court that such an event actually occurred. A mom-and-pop store wouldn't be within scope of this.
And the same for online businesses.