Your "question" is c0cked and loaded. I thought I might try to pull the point out from between the lines of your "question", but I can't be certain about the point to why you asked the question. So what I'm going to do is just clarify the difference between the OGL and the GSL regarding people's general buying preferences.
First, allow me to point out that most people don't buy a product to spite a particular company or to support a particular kind of business. Sometimes they'll buy a product to support a particular company they like, but usually it's dependent on the product itself.
The OGL did indeed allow a greater support for 3pp's to multiply. It allowed plenty of room for companies to compete and come up with unique ideas that distinguish them from their competitors. If someone wanted to support D&D, they could, but mostly they were free to do what they wanted.
With the GSL, it limits the pool of publishers, because it's not a generally good idea to support a competitor's product, which is exactly what the GSL encourages: supporting the D&D system. If you, as a publisher, support the game, it typically means you're willing to take a smaller cut of the pie to ensure that you have a steady market to dip into. WOTC's success becomes your success. If you want your game to survive, then you have to do everything in your power to help the D&D system to grow. The GSL ensures that your game system has little variance from D&D, because you're not allowed to redefine the definitions. If there is any mechanic in the system at all that you want to use, it must direct the reader to the D&D core rulebook where it is found. You can't even have humans without referencing the D&D core rulebooks. (Though you can get around that particular snaffu by declaring them "Baratas Humans" or something like that.) Essentially, every single product produced must be nothing more than a supplement. So, then, if you buy that product, or better yet, if you make your own little world using the GSL, you are supporting D&D, period. Even if you never buy another D&D product, but use a GSL product, you are supporting D&D because you had to buy the D&D core rulebooks to use that GSL product.
So, then, as a customer, my preferences are virtually irrelevant. Either I support D&D 4e, or I don't. If I buy GSL, then I am supporting 4e. No if's, and's, or but's.