I suspect that the real reason is that brake wear is directly propotional to application pressure.
For those of us that fly aircraft without auto brake, ther is generally a notice somewhere that reads similar to:
"These brakes operate best at high temperatures, use 600psi per side, unless otherwise warrented"
Now pilots being what they are may or may not follow such a notice - solution: intoduce an automatic system that applies the cheapest amount of pressure (read minimum wear per landing).