I like the airdrop feature of Pundi. Why have they chosen such an interesting scheme?
Pundi X says: It reduces the risk of token's falling at the exchanges
Rather a smart move to cope with the fluctuations after listing. Do you know what are the exact exchanges for PXS token to be listed?
how does help to keep the rate?
I think token holders will hold PXS token in order to receive more tokens through airdrop.
I think this is the scheme.
You are right, this is what Pundi X can suggest

They have the airdrop (bonus token) to everyone who holds their PXS token monthly in 3 years because there are only 20% tokens for this public sales, 10% for company and advisors, the rest 70% will be for airdrop monthly.
So to have max amount of tokens, token holder must hold it for 3 years. If they sell it before 3 years then it will be a disadvantage for them because they cannot enjoy the airdrop anymore.