Your cover photo is what I now do in nearly all the classes I teach. (I use a real single dollar bill, not a stack of fake $100s).
First of all, it wakes everyone up and evokes a strong, sometimes violent reaction. It is interesting that people react more violently to burning a dollar bill than spilling a $5 coffee. They consider money to be sacred, something to be worshipped, not destroyed.
The educational value of burning a dollar bill is to ask the question: WHAT JUST HAPPENED? Or specifically: IS THERE NOW LESS WEALTH IN THE WORLD?
The correct answer to the specific question is NO. Money is not wealth, just a symbol of wealth, used to move real wealth. As you point out, that movement under capitalism goes inexorably from those who work and create wealth to the rich who don't contribute anything.
The answer to the first question - what really happens when I burn a dollar bill - is that I just made the dollar in your pocket a trillionth (or whatever)of a cent more valuable. Because there is one less symbolic dollar of wealth in the world, but the amount of wealth has not changed, that symbolic dollar now accounts for a greater share of the real wealth in the world.
So cry when someone spills coffee, but cheer when they burn money. Value the labor of those who create real wealth, not the tricks of those who steal it.