They're just giving it away as a gift though, nothing to do with their post actually. Only the legendary people with the outmost knowledge of bitcoin can only receive such high merits. And yes, as long as the merit source find it very useful and unique I guess, that will also be considered to receive a high number of merits.
To make it short, it all depends on the Merit Giver.

Edited: Nice thread out there, you can also give us the top 200 users who received a large number of merits as I think ( or is it already done by somebody?  )