Because festivals are [mostly] known variables? Can they play Red Rocks or Hollywood Bowl? Yeah sure. I'm not going to spend much time thinking about it but if you want to put together a fantasy itinerary go right ahead.
And outdoor shows in the short term seems perfectly logical to me given TR's family, the families of the rest of the band members (and I assume crew), and the comments that have already been made about being careful and not rushing it. You're free to disagree.