Organic weeding
Okay too much salt is bad for your soil, breaking down the structure in something called puddling. Would imagine that over time it would also work to the detriment on brick.
It has been tried on weed growth between paving stones and reported to have worked by the Facebook commenters BUT
it needs to be used on sunny days for it to work.
Makes me think of my mother with a small brush, painting Roundup on dandelions in the lawn.