I ran this by a professor of law at the university. I don't think he has ever watched a TV show in his lifetime, but his take on it as a generic question is...
Realizing that, in the US with our somewhat asinine civil system, while you can sue a person for having dyed hair if it offends you, bringing such a lawsuit does not usually equal winning the lawsuit.
A company has no legal standing to prohibit the generic display of their logo, if the product is displayed in a normal setting. i.e., you can publish a video on YouTube on how to program While Loops in Perl, and the fact that your MacBook's glowing apple is visible in full glory does not violate copyright or trademark laws. That is like the "you have no expectation of privacy in public" type of situation where someone's camera sees you entering the adult video shop.
(I decoded this as sort of a "fair use" for cameras. And I sure hope he is right. I make lots of programming videos that I post online and I brag about my Apple in them.)
Merely showing a logo in a video is not a breach of trademark or copyright. If it were, then Hollywood could never use a camera in public. If it were a breach, then Joe's Cajun Tacos could sue because his sign was shown in two frames during the high speed car chase. And so could every other business up and down the street, from the start of the shootout until the bad guys get their comeuppance at the end of the chase.
(And in my amateur opinion, I have absolutely no doubt that there are many lawyers who would jump at the chance to bill a blockbuster movie for showing their client's sign without permission.)
Again, even inside shots that showed a stray Dr. Pepper can, a bag of Planters peanuts, or suchlike could start a chain of legal problems. For that matter, what if you take a picture of your kid's birthday party at the playground of McDonalds. Do you owe them money because the twin arches in your snapshots? How about that coke can that your child is holding? What happens when it shows up in public on Facebook?
According to the Broadcasting and Cable magazine, it is now business as usual for a production company to approach a corporation with the offer to showcase their products. For money, of course. And if they refuse, then their logo will be covered or blanked out if the item is necessary for the movie/TV video, but most often, another product from a more amenable company is used.
But, once again in the practical aspects, and harking back to our freedom to sue for anything, a deep pocket corporation can destroy a smaller company, even if the suit has no merit, and it has been thrown out by the courts multiple times. Even a state with SLAPP suit laws can sometimes only partially protect the victim.
...END of professional opinion...
So, (my opinion again) some of the product blurring may just be from legal advice from their lawyers.