[acchow]

If it's on your skin, what's the advantage of using this over, say, 50% isopropyl alcohol?

[alvarezbjm-hn]

A strain which can cause necrosis in a healthy individual goes under your skin, where not enough alcohol can penetrate.

Again: most strains of S. aureus can not cause a serious infection in someone healthy. Antibiotic abuse drives the selective pressure towards resistant strains.