These bride costs should be allowed to climb infinitely, because it will serve as an incentive for families to have girls - and actually sex-selectively abort boys.
Unfortunately we are seeing all this in the West, where Asian migrants to countries like Australia are still selectively aborting girls. The difference is that other ethnicities are not, so those Asian boys can then grow up to marry girls from other communities, and a female shortage is pushed onto the whole of society. Its basically a tragedy of the commons.