These are the folks who are making good money. Some more than others, but each of them will be marketing from their own domain. You can still link to the self replicating site you were given originally from your site to make sales. You are just out of luck. With your own website and domain, you can control your own meta tags, you can control everything.
Search engines give far more weight to sites having their own domain.
Freebie websites often won't get listed either. Most search engines limit the amount of pages from any given domain that they will list. This is one thing you can do yourself. It's totally in your control. Don't lose your name.