Right, sure, and that game is not lifting the market, generally speaking.

Other market makers are often moving away from something they've seen but you haven't yet. When whatever that is hits you, the fills you got from the other market maker will look really bad.

Sure, but those short-term active strategies have little impact next to what big paper will lift in major macro markets.

Not sure exactly what you're trying to say but let me tell you, fills from other HFT firms are highly toxic.

Not aware of a market maker that also doesn't take liquidity as well. In fact, it probably would impossible to market make without also taking (you wouldn't be able to provide liquidity if your quotes were in cross with the market).

That said market makers do a lot more making than taking.