Emily cultures staph too and her clinic pretty much says the same thing; they only treat it if she gets sick and it causes problems. Otherwise, they leave it alone.
Before going straight to antibiotics though, at the first sign of illness we are to start sinus rinses (which, fortunately, Emily tolerates well!) and increase her neb(albuterol) and vest to 3-4x/day. If after a few days she is still getting worse then we need to call the clinic and talk about it.