So I live in a highly saturated area of controlled airspace. I've never had a problem flying wherever and whenever I wish.  Two simple phone calls to the local Air Force Base and the local major airport and I'm good to go.
I've developed a rapport with most of these guys (ATC) by now, and at this point it's usually a "hey how you doing? where and when?".
The thing is, I'm a part 107 licensed pilot as well, and cannot use any of the footage from any of these flights for commercial purposes. I've often been very frustrated for that purpose and then wonder why if it's so easy to gain ATC authorization, we have to go through such a process to fly commercially at the same locations.  
After much thought I came to the following conclusion. There are way too many non-compliant Pilots out there that the amount of illegal footage would be so overwhelming there would be no way that authorities would have any way to keep it under control, or even able to prove anyting about not having authorization. As it is now boils down to, do you have it in writing?. simple easy to prove just right now authorities are overwhelmed as it is and unable to keep everything under control currently. But as time goes and we're able to prosecute the rogue Pilots then Simple Rules such as this (keep it in writing) will be a great benefit.  
so I guess I'm just saying I support the current Troublesome processes that we have to get authority to fly in class B C D airspace but it's all for the protection of our chosen field.
Thoughts anyone?

That’s the best thing a person can do,  just ask permission , I do that even if I know that I am legally able to fly, if I go across someone’s property I just ask permission , never have I ever been refused.

The reality is, if no incident occurs, no one is interested in checking and enforcement.
If the pilot flies in an area they shouldn't and it is noted by an official, a judgement has to be made about where is the harm. The harm might well be monkey see, monkey do. Ie some other idiot might try it and cause an incident.

I do some real estate aerial photography.  There have been occasions that the neighbors get a little testy if I am flying over their house, even though the camera is not recording their area.  So I do try informing them on what I am recording, and I can show them on my laptop the flight.  Most of the time it is education, and sometimes, oh boy I better get done and out of here.  Permission is the best choice.  Good luck!