I was just thinking about this whilst walking through the office and seeing the dozens of monitors with rather large "Dell" letters on the back of each one.
We're paying for the product, but we're also offering such companies free advertising.
e.g. Apple having the Apple logo on their products, Samsung having the word "Samsung" on their phones, TVs etc.
Just seems strange to me.
I've thought about this before (in fact, I just got into a discussion about it a few days ago at work), but I really only get annoyed by the concept when I think about things that do not matter to me, like shirts. I do not buy name brand clothes to flaunt money or fashion sense, rather I buy them for their fit and feel. My coincidentally-Polo-branded polo shirts are in my wardrobe because they feel really nice and they hold up well, not because they are Polo. I want their brand on my clothes somewhere, but on a label somewhere on the inside, so when it gets destroyed in one wash, then I know what brand to stop buying (or to wash properly...). Though, I think I have grown to like the little polo jockey, but I cannot stand the large version that I have started to see; I think that crosses the line to flaunting (or trying to flaunt).
With electronics and similar products (cars), I think that it makes a bit more sense because it makes it easier to describe them. People cannot report a "blue car hit me" to much utility, unless it stuck around, but they can say a "blue Ford Fiesta hit me." Similarly, if (when?) my low end Dell monitor breaks, I know who to blame or who to call for support.
I think I like Kami-'s interpretation of it best. Not only do we need it sometimes, but it shows a bit of pride in your work. If you won't stick your brand on it in a subtle, yet prominent way, then it sounds like you do not stand behind it. Certainly, when the product looks good, having the logo helps to expand their brand, but I do not mind giving someone props when they deserve them. For example, my two Dell monitors are 19" 1280x1024 pieces of garbage hooked up to my solid looking, but similarly garbage Dell laptop. I can visibly see a difference in the color of the two monitors, and I can even consciously notice the refresh rate of one of them on a recurring basis. That's their brand on these things, and I mention that to people when they visit my office if "how do you like it" comes up.
Of course, Dell does make some of the best monitors at the high end of the market--I know that--but they do themselves a huge disservice by pushing out the garbage on the other end, which companies like the one that I work for turn around to buy/lease for its employees. Combined with how truly awful their warranty services are, I will be hard pressed to ever buy a Dell product personally. So it's a double edged sword: we are literally paying them to market their product in a way, but I also have something to point to when it sucks.