MAL: Boros is too big. It's crawling with Alliance.
Ares, one of Boros' moons, is home to Alliance military shipyards. Up to five Alliance cruisers can be seen being constructed in orbit around Ares any given time -- these take about six years to complete. The Alliance presence here is as large as it gets outside the Core.
Boros is known for its' scrap metal industry. Much of the overstocks, castoffs and junk from Ares finds its way to Boros, much of which can be had for a decent price. Merchants appreciate the few landing restrictions on Boros.