So let's look at this situation. It's a shop page, shop.{clientdomain}.tld. Now you need SSL for this, using AWS you need a TXT record from their ACM. You also need a CNAME to your domain (ideally) or to a Cloudfront instance. For your customer you now need them to make 2 DNS entries. This is from my experience having non-profit like entities setup DNS.
- Well the person who set that up stopped responding, isn't there another way to get this going?
- I've added all the record in what do you mean they don't match?
- I don't even know what DNS is, why is this necessary?
- I added in the record but the system didn't take one of them because it started with an underscore and they said that was invalid.
- We just switched websites to WIX, why is our shop page not loading, is your system down?
- Will this break my email, I don't want it to break my email.
- Here is my login, just go in and change what you need.
So in all, it's not just $10, it's a significant investment in time and resources to do this "simple" change that until this point did not have any downside. Hindsight is like that every time.