When people have had enough:

So when the (mostly white?) patrons of restaurants won't take their Sunday brunch being interrupted because some black activists are concerned about (black) thugs being detained (and when they resist, being shot) by police for acting like thugs, then what happens?

Those activists get chased out of the restaurant by angry white people who are tired of the bullshit and harassment and double standards...that's what.

 "White lives matter too!"

People, especially law abiding white people who aren't racist are beginning to tire of the bullshit. They are tired of being called racist and tired of having their "White Privilege" shoved in their faces...They are (mostly) not racists, and their "Privilege" happens because they are hard working, law abiding folks who don't squander their money or their opportunities...and they know it. They know they aren't the issue, but the Black community and society is

The backlash is coming. This is but the opening steps.