It's arogant because you expect it to be second knowledge. ...
Then you don't know what "arrogant" means. Not only do I not expect flag display knowledge to be second knowledge, I'm fully aware that most people aren't aware of the protocols of flag display. You think the rules are highly complex, and because I find them logical and simple to understand, you think I'm arrogant simply because I admit they are simple to understand. That says far more about you then it does about me.
Like I said, the rules are such that they give the American flag the most THE most prominent honor possible - all the details stem from that basis. Once you understand that basis, the rules themselves become quite logical, simple and easy to understand.
There are those who don't want to bother with learning the why of the rules, and focus solely on the rules themselves, and it's those people, generally speaking, who think the rules are a complicated mess. As a result, they tend to latch onto the simplest rule they can understand, such as highest and in the middle, and want the rest of the rules to be as simple as that. They freak out at flag patches on shoulders of uniforms and don't understand why on one shoulder the flag looks fine but on another shoulder the flag is backwards. If they understood the "why" of the rules, they wouldn't be confused by the complexity at all.
Go back to the BSA web site and take a close look at the rules you posted the attachments of. Note the layout of the flags next to each (that you cropped from the paragraph). For example, permanent, free-standing, separate flagstaffs are not the same as flags which are typically "grouped" together. And in Section 3, paragraph "C" down below on that page explains the rule in detail with "...if on the same level..." which is how the flag poles are in the picture in the OP.
To me, those rules seem very simple, not complex at all. Not because the knowledge should be second nature, but because they make perfect sense. It may also very well be that I had to pay more attention to the rules because I was a bugler in the Boy Scouts. One of the seemingly odd responsibilities of a bugler, be it one in the Scouts or in the Navy as my father was, is knowing all of the flag display rules cold. But I certainly don't expect everyone to know them that well. I expect them to know them as well as you thought you knew them, actually.
Knowing the rules cold is both a blessing and a curse. It's a curse when I pull up to a shipper (or one particular freight forwarder in Laredo) who has the American, Mexican and Canadian flags flying in front of their building, with the American flag flying highest and in the middle, and I wonder how the Hell they could continue to fly them that way without someone saying something. It angers me when I see a grossly neglected, badly faded and tattered American flag flying in front of a place of business. It makes me wonder, if they are that lax and negligent on such an important thing, how are they with details of their own products and their own people?