Something I have never really understood (perhaps someone can help clarify), why does WotC put so much emphasis on making products for tournament and gaming-store play rather than straight-up modules and sourcebooks? Does the tournament/store material actually bring in money?
As others have said, this is widely done. There are now so many organized play programs that good active stores have several events running nearly every day (often for different programs). A store might have Friday Night Magic, Wednesday Adventurers League, Pathfinder Society, Attack Wing through WizKids, FFG events, 13th Age, etc. Many of the programs are more expensive to run than small RPG companies make! In the 90's (I forget the year) the RPGA said it needed $2 million to run well.
It is advertising, and it can be effective. There haven't been 'scientific' studies done publicly, but I know of one private one during the Living Greyhawk days that seemed to suggest a huge correlation between sales and organized play. I also tend to think that the success of the Dark Sun line (as the best selling setting for 4E, beating out FR handily) was tied to an almost perfectly planned organized play program (and the absolute least of that was Ashes of Athas).
Friday Night Magic is the model every company can look to. With Wizards support, that program alone carries tons of stores that would otherwise not be profitable. It literally keeps the doors open and feeds tremendous revenue back to Wizards. Every RPG company would like to figure out how to mine that model for RPGs and go beyond advertising and solidly into generating revenue.
Exclusivity sounds bad, especially to those that don't take the steps (or can't) to get the exclusive thing, but it is a huge motivator for many. Exclusivity can be fantastic for driving interest.
Every organized play program tries to balance different factors: exclusivity (Adventurers League's Wednesday Encounters program now uses the same adventure stores sell on shelves, but Expeditions requires a commitment to run a game in public), advertising and direct revenue (often tying organized play to new releases), accessibility/flexibility (home vs convention vs store), etc.
confirmed that Expeditions are not available for home play, only public play. There was discussion of what constitutes public play in an earlier thread, and it was basically in-store, at a convention, special event, etc., as long as it's public.
You are correct. Expeditions adventures (such as Defiance in Phlan) require that you contact Wizards through the support page and tell them the public location where you will run them (instructions are on the AL web site). It can be a store, a library, a school, but it has to be public. The point of the program is to grow the player base. If you want to just play through 20 levels of D&D with your friends at home, you can run the official published adventure and still be part of the Adventurers League. Encounters uses the very same published adventure, but it is run in phases each Wednesday at a store. This allows anyone to go to the Wizards site and use the Locator to find a store running the program and jump into a D&D game. It keeps support strong for the stores.