Supreme Court rules for web designer in LGBTQ protections case
nbcnews.com
nbcnews.com
If a random web designer refuses to offer service to you... there is no big deal. There are countless other web designers that will offer you the same service.
On the other hand if Amazon refuses to offer services to you're pretty much screwed. So they shouldn't have this right.
This is a extreme example, but as a rule of thumb: the bigger the company is, less it has the right to randomly refuse offering service to a paying customer. The smaller a company is the more rights it has to do refuse anyone just because they feel like it.