I can't see how it doesn't affect options liquidity. Timber Hill was a pretty big firm if I recall. Maybe things have changed. If they aren't earning then it's probable others aren't either.
Well it's ALWAYS more profitable trading against your clients that's why retail forex is littered with bucket shops. I just can't believe Options with everything supposed to be traded on central exchanges are still resorting to bucket shop market-makings.
nth power.