These LRADs have always been planned to be used against mass protests, from day one.
The imperial boomerang: https://en.wikipedia.org/wiki/Imperial_boomerang
If you see injustice but do nothing, you invite the same injustice on yourself.
Injustice at it's core is an arbitrary execution of power, so suffering injustice anywhere is to let power stay unchecked which communicates that there are no consequences for abuses of power, which only invites more abuses of power.
If there aren't consequences for power being used against others, there won't be consequences for power being used against you.