Reddit couldn't work if upvotes were worthless. Upvotes have a time value associated with them. Also there is a market for them. A quick google for "buy redd

Reddit couldn't work if upvotes were worthless. Upvotes have a time value associated with them. Also there is a market for them. A quick google for "buy reddit upvotes" exposes a large grey market facilitating the exchange of upvotes for cash. Everyone can vote on everything once is also suspect, since many users have secondary accounts. So at reddit, voting is already tied to an incentive like BTC, and until the censorship incidents it was working rather well.