Hive SBI is an account-based curation program with a deep history. It only looks like vote buying if you give a very cursory look.

Yes, the program's curation income is paid back to the accounts that sponsor others, in the form of upvotes on their own content, but that means half of the value goes to accounts that paid nothing (were curated for upvotes by others!) and the majority of members have never paid anything at all for votes.