Yes we do. It is of no benefit to the players, and of some detriment.
As Westdene Seagull pointed out, the players need to retain a warmth, readiness and physical metabolism which 30 minutes' rest will only hinder.
Quite. When it was extended from 10 to 15 minutes, that was purely at the request of the TV companies. The managers and players never wanted it; indeed some managers stated that they can say all they need to say in 10 minutes.
Anyone who wants anything longer than 15 minutes is only doing so...