Like so many visuals, it's limited to the biggest upvoters. We have a lot of smaller accounts that have us on their steemauto or steemvoter, and we appreciate all the upvotes from small accounts, too! We've received more than 3200 upvotes in the last month, from 730 different accounts. It will be higher when we are more regular with our updates, because then the people with subscriptions will provide more support (and receive more benefit from providing that support!)
And yes, it's awesome the way Steem builds all these unique individuals into semi-cohesive communities!