Absolutely. The more ideas being thrown at the wall, the better the likelihood something will stick.
The Home Depot shoot was the most daring of all. From what I can tell, the shooter had to have been in the garage. Just too must terrain around to make for a good shoot unless he was in the garage.
A local FReeper, can't remember who, posted a few days ago that he'd gone out to the Home Depot. He was more familiar with the area than some of us locals (though I could tell you anything you wanted about the Manassas location). He walked around the scene very carefully and deduced that the shot came across Hwy 50 from the school yard. That was also an area of interest to police, though by the time they really did some looking over there, the media had contaminated the area, because the fraudulent witness had indicated that the shot came from within the garage. So while police are combing the inside of the garage, media set up camp from the highly-possible-to-likely site in the school yard. Dang, wish I could find that post by the guy who visited the site several days later. It was a real good one.
Agree with you entirely on the fact that the shooter is taking the opportunity that gives him the best chance for a kill. You know, he picks out the spot and then waits for the opportunity to present itself regardless of who the victim is. I'd venture to say the guy probably takes his time, maybe trains his sights on a numbers of "possibles" before he ever takes a shot. I would imagine this would be quite a thrill for him. "Will you be the one to die right now, black lady shopping alone? Or maybe it will be this nice elderly white gentleman. Nope, I think for tonight it will be the middle-aged white guy talking on the phone. He looks like he's ready to die now." Guy on phone presents himself in a way that makes him an appealing shot, and then guy on phone is lying between his car and the gas pump as the shooter breaks down his gun and saunters away calmly, either to drive himself home or to have someone drive him because he's too hopped up on the adrenaline of his power to do it himself.
Also agree that his message is that we're not safe. That he holds all our fates. Much better to captivate a large public with uncertainty than to wield power over one single victim at the moment. That we're all jittery and even the sound of a gas pump shutting off can make us jump must be known to the shooter, and must give him a thrill that one single person's pleas and cries cannot. He has us all in the palm of his hand - not just his prospective victims, the regular public, but also the power-wielders heretofore: law enforcement and the media. He truly IS a god. And he lets us know this by letting us see how elusive he is, and how he can do anything that media/police tell him he can't do. Keeping the schools safe? Whoops. Nope, schools aren't safe now. Not safe to pump gas, but safe to shop? No, 'fraid not. Not safe to go out to eat. Not any safer now that the military is assisting. Nothing is sacred to this guy, and everything that media/police say he hasn't done or can't do, he's gonna do.
I would speculate police killings or some more high-profile killing forthcoming. Also wouldn't be surprised if he starts getting people as they're driving. Or coming out of their homes. Or something else that, for the moment, we feel more OK about doing than pumping gas. See, we feel all right walking out to our cars in the morning - but if he knows that, he'll do anything he can to wreck that. It gives him more power, and sends, yes, that message that there is no place we can hide from him. He holds us in the palm of his hand, and he wants us to know he can make a fist and squeeze anytime he pleases.
About this, the guy tried to shoot through glass early on, but missed his shot, it's thought. Glass throws a monkey wrench in the bullet's path, so last week people were being advised to drive with their windows up. The shooter/s can't be sure of hitting their mark that way.