Well, it's not that sparse here at least. For H3, there were about a dozen of us, and my friend and I were the 2nd and 3rd people to get the game. Contrast that with the fact that there were 3 large pallets of product, including at least 30 or so legendary editions and a couple hundred standard and le or whatever.
For Reach, there were maybe 20 or so people, everyone was just chillin' and actually just excited for the game (unlike the 100+ people lined up freezing outside Gamestop - which SHARES A PARKING LOT WITH THE WAL-MART). The WM employees brought out Halo-themed drinks and cookies and stuff. Everyone, no matter which version you got, recieved a Halo: Reach beenie cap, lanyard, etc. They had prize drawings. And, to top it all off, everyone that bought the game at midnight got $25 off at the register.
Say what you will about Wal-Mart, but at least in my town, they know how to throw a Halo release party