Well the D in IDPA may stand for defensive but any organization that requires you to run behind a barrel before you can even eject the empty magazine from your firearm and says you need keep a malfunctioning magazine isn't fully based in reality.
They are all games, they have timers, rules, rankings, awards, and national championships, and the people who are good at one are typically good at others since they know how to run a handgun well.
As for a class costing $1,500. TDSA charges what, $400 for a 2 day class with 20+ hours of instruction by the best teachers in Oklahoma.