I'm aware. But one of the "selling points" for premium is the curation from leo.voter, so it would be a bit strange if a premium user with no LEO didn't get any votes.
I curate a bit, but in general I think it is (or maybe "was") better for me to delegate 😊
U don't know how they do it, I also had such experience with my last premium subscription, sometimes no single vote for 2 weeks. But when they come, they can give you votes back to back for a week long.