I guess I think rather simplistically. If I were one of these manufacturers, I would love to see my brand name out there and I find it hard to believe that these calendars or T-shirts would threaten the ownership of the logos... but then I'm neither and attorney nor particularly litigious.
Branding is a very powerful sales tool.
The manufacturers want to control the association of their brand logos. This is done by using fees for use of the logo. This way, they can charge minimal fees for uses that associate well with their logo and excessive fees for those associations which cast them in a poor light. You'll see more of this control as the Web and vehicles like You tube become even more popular and useful as a sales tool.
Advertising uses association to make you feel good, either subliminally or outright, whenever you see their logo or brand name. This leads to consumers preferring their brand and being outright loyal to the brand name/logo. This equates to sales dollars.
For example, if you post a picture of a dog pile with a company logo on it, the logo owner may demand you remove it, as this association does not advance the logo/Brand, and the logo is something you do not own or have legal control over. The more people that see this picture, the more strongly you can expect legal action.
In order to retain control of said logo or brand name, the more vigorous you need to be attempting to control said name. Since, when these matters come before a court, incidents where you obviously ignored such control will be seen as detrimental to your cause. And, the particular incident may be interpreted as you holding a grudge against a particular party.
This is a natural occurrence of a litigious happy society. And, the desire to get something for no or little effort.
This is also happening in the model airplane industry, too. Scale model airplane manufacturers are now seeing demand for royalties from sales of model kits, too. There is not much margin for profit in these things and the fees manufacturers are asking, either adds significantly to the sales cost or makes kit manufacture completely uneconomical. There is still some debate over whether the likeness of the completed model is actually copyrighted. But using, say, the Cessna name on the box or decals incurs royalty fees.
Cheers,
