If Walmart colluded with all the other major grocery stories to ban anyone who wants to raise their taxes, for example, then I would find that pretty horrifying

If Walmart colluded with all the other major grocery stories to ban anyone who wants to raise their taxes, for example, then I would find that pretty horrifying as well and would advocate for laws to prevent that. Fortunately, we aren't seeing such actions yet, so we don't really have a large need for such laws. But yes, if such actions happened, then that would be bad and we should make that illegal.