to provide a Web site interface and/or templates, because then when you want to switch hosts, you most likely can't transfer your Web site because it was created with their proprietary software.

Keeps things separate. Buy a domain from a domain place, buy hosting from a hosting provider, and then use an open source software such as Wordpress (with hundreds of free templates) to manage your Web site.

A good hosting account goes for about $4/mo. And usually you have the ability to upgrade space, bandwidth, etc as needed. That way if your traffic increases, you can increase your plan without any hassle.