You got a valid logic there, but at least,shouldn't they make the energy regenerates faster, not 3 for every 30 mins? It just too long for people who wanted to play this game longer.
No one said the game is hard or anything. It just we want to play to our heart content, not playing every 30 minutes once. Or need to wait until shit is full and play for full 40-50 minutes and that's it. You just couldn't accept people have more time to play than you do.