Again, as I've said before, the recharge doesn't matter when people play with shift on and can switch out after killing something with one of those moves, along with Hyper Beam and Giga Impact...
While I can understand making them available so that weaker starters can use them, as Spade said, that also means the stronger starters can use them. Serperior and Blaziken might not be able to make the most of them, due to them relying on setting up, while physical Pokemon like Torterra would prefer other moves, starters like Greninja and Infernape could easily use them to kill something and switch.
oh, and ik that the ultimate moves are post game in D/P/Pt too