Well, with Grin's current monetary policy I can't say I'm suprised. People have been complaining about this since day 1. Pretty legit concern also, since all coins will be close to wortheless over time. (Dogecoin V2.0?)
How can they say 0.2% premine when the coin supply is infinite? The actual amount is nowhere to be found since there are no explorers yet.
It seems to me as an effort to capitalise on GRIN's popularity and on people's fear about its emission. There's no website, no explorer, no community... behind this could be a single person who's planning to dump the premine on the first exchange and disappear.