Although using a real name, or website name, as username is not recommended it is also not limited to staff members.

A real name is not recommended for privacy reasons, even if you do not see the need for privacy when registering. Once posted in the internet, your real name will never go away anymore, even not after a name change as there are also sites that keep historic versions of websites.

Using a website, or company, name is not recommended as this might change in the future and for various reasons the site where you have registered may not be able or will not allow for username changes.