Although you are right in the technical sense, I don't agree profiting from other peoples work on moral grounds.

For example: http://www.illusionmage.com/ is a site that will sell you a copy of Blender, with a rebranded logo. Because Blender is GPL, any modifications must also be GPL. So the author of "Illusionmage" created a patch (available http://www.illusionmage.com/disclaimer.htm) and now sells the whole package for 47$ a pop.

Although this technically complies with the GPL, I find it abusive of the GPL on moral grounds. I must agree with you that indeed selling GPL is allowed in the technical sense though. -H