Will everyone who wants to boot people out of an arena when inactive please remember a couple of things.
A People in the tower are not necessarily just "waiting".
B They can be planning an attack, choosing a plane, or any one of a number of things.
C There are very few people who deliberately just walk away from their computer hopeing to get a few perk points.
D You are asking HTC to kick off their customers. Starting a Public Relations nightmare of epic proportions.
Not to mention epic whining.
Its just NOT going to happen people. Get over it.
And remember, every time your in the tower for 30 seconds, someone may be wanting to kick YOU off!