$3+ is likely to be people using bid-bots to promote their answers. You can check this by looking at the list of user names in the upvotes (on a site like busy you can see the amounts upvoted and you can cross-reference to steembottracker).

Musing maximum upvote seems to be 25% of their power which is currently close to $0.90 - $1.00. So this is what you would expect from a really good answer, plus a few smaller upvotes from other Musing users.