Two things are at play I think: 1) Very popular sites have lots of users rushing to submit anything they publish = a free upvote each time 2) Early upvotes ar

Two things are at play I think: 1) Very popular sites have lots of users rushing to submit anything they publish = a free upvote each time 2) Early upvotes are very important so if you can convince two or three people in your personal network you will get much more exposure