What's dropping each day?
http://www.expire.biz/
Most domains do get snapped up immediately by snapnames or enom for example, who will hold onto it for a few days while tasting or offering it to others at auction, etc.. before letting it go.
Check for yourself. Take a name like 0190-700300.com for example. Registered for tasting by Snapnames. Same with 123paixnidia.com. Try any of them!