They have done nothing wrong..... it was a non violent protest. Some Chelsea fans I'm embarrassed say clapped.
There are young players bending the knee because they are so scared that they will damage their careers. Staff are bending the knee because if they don't they will loose their jobs.
As for fans they have designated seats to their name that they pay a lot of money for. They are scared of loosing their season tickets, so they won't boo. otherwise a lot more would boo.
I would say turn you back on the pitch in protest.
The sport of rugby has it right. During yesterday's Eng v France international, as they lined up before the game only half the Eng team took a knee. No media headlines of shock/horror against the individuals. If football followed suit and let the individuals decide on whether to take the knee, it would go some way in placating the boo boys.