1. Right now, these coins pumping with high fees are largely because retail investors aren't taking the bait, so they're trying to lure arbitrage players into the market, or even the exchange's proprietary trading MM. These guys have deep pockets and can drop big money... 2. Experienced MMs and newbie MMs can easily spot the pumping techniques. Some can keep pumping non-stop, while others have cooldown periods—this is the difference in skill level.