I read about needing to apply grease to bushings on antisway bars. WUWT? We don't have to grease our OEM bushings (or do we have any?). Somebody enlighten me here. What's the difference between an aftermarked ASB and the OEM that requires grease?

aftermarket tends to be a larger sway so it's tighter, increasing squeaks/sounds/noises. hence the resorting to greasing