It's a nice gesture but it's not currently easy for people to 'claim' Lumens. Plenty of people want to claim but depending on which wallet software they use have to track down their addresses, figure out which wallet supports signatures, import into that wallet and then sign each one individually. It's cumbersome and not sure why it has to be 'that' cumbersome.

(Note: Some people can't even claim Lumens at all because of their wallet-type, ex. coinbase, circle, and other wallets that don't support signatures). I just can't help but feel there were more efficient ways to do this than this method which wants to target bitcoin holders specifically and that this was a way for the company to 'get' lumens, knowing that plenty of people wouldn't be able to claim by default giving it to stellar.