Just so you know, Light Monkey was shaken down on a recent depth attempt. "If you don't sponsor us to the tune of 3 grand, we will cover your logo with duct tape so no one sees your logo".
I think it is sad that this would happen. I only hope that light Monkey told them "thanks for using our equipment I am sure you made an excellent choice and we will happily supply the duct tape".
In the real world of marketing this is very commonly done, albeit with a greater degree of tact... on both sides. Ever watch a TV show that ends with voiceover/text saying "Promotional consideration has been provided by..." Variants include Product Placement, Product Integration, and traditional Promotional Consideration.
Typically one of two things happen:
1.) Where a product is "one of multiple acceptable products" the opportunity to supply product and pay a product placement/integration fee is offered and whichever brand agrees to the most lucrative deal gets their product used.
2.) Where there is a specific product desired - or no alternative - the opportunity to supply product and perhaps pay a product placement fee is offered to that one company. If there's interest, there's negotiation. If a deal is struck, the brand is shown. If there's no deal... the brand is struck. (Usually with something better than duct tape.)
Also note, any time ANY product is paying a fee (including simply running ads during a show) it is common to strike the logos of any/all other brands that can be seen in a production. It's simply not fair to anyone who is paying to have THEIR brand featured to see other brands featured as well... for free.
Ultimately, I guess whether any brand/company feels like they were "shaken down" comes down to a matter of style. Done properly, Light Monkey would have been "offered a promotional opportunity" that they could have either accepted or declined.