The rules DO allow for advertising in most cases, by the way. In the NOR or SIs you will usually find the designation of an event as allowing or not allowing advertising. Rarely these days will you see NO Advertising.

And many folks are not really sponsored -- they often just buy stick-on decals that shows their own company's name and url.

There are a rare few that have landed a good sponsor, but don't hold your breath when trying to find such a fairy god father/mother.

Rick