What's wrong with people... Why waste money on a VPS? Do you know how to run a server without a control panel? Or do you want to pay ten times what you're paying now for a VPS plus licensing fees?
If your current provider has plans available with a higher bandwidth allowance, take advantage of it... Shared hosting is cheap these days. If your website's traffic is increasing to the point in which it's causing an issue for the other customers on the server, I'm sure your hosting provider would let you know.
The entire webhosting industry seems to be ran and managed by mindless drones these days that are incapable of thinking logically.