Many people are probably letting them in, and I can't say anything about this one for sure, but I know for a fact that in the LA case, (bear mountain, believe it was) the police openly admitted to searching empty cabins, which means no permission was given, and certainly, a warrant for every cabin in an area is far from reasonable.
I was also hearing on the radio things about "police are now allowing people out of their homes" or "police are allowing people back into their homes", depending on the situation, and many of the media reports sure made it seem like many people were forcibly evacuated.
And I want to point out that this guy was found by a homeowner, not by the police, and he was found by this homeowner only after this lockdown was lifted, according to what I heard on the radio at work.
BTW, how do cops in a city teeming with tens of thousands of LEO get in a gun fight with two guys, and then lose them? Honestly, what kind of ineptitude is that? These are the guys we let run around with machine guns?