“Part of making a market thick involves finding a time at which lots of people will participate at the same time. But gaming the system when the system is “first come, first served” can mean contriving to be earlier than your competitors. That’s why, for example, the recruitment of college freshmen to join fraternities and sororities is called “rush.” Back in the late 1800s, fraternities were mostly social clubs for college seniors. But in an effort to get a little ahead of their competitors in recruiting, some started “rushing” to recruit earlier and earlier. Fast-forward to today, when it is first-semester students who are the targets of fraternity and sorority rush.”