That's not a surprise and it doesn't make steemit a superior coin. There are a lot of coins that are used multiple times more than bitcoin as bitcoin is being treated exclusively as an investing coin. Bitcoin can't compete with Ethereum for number of transactions and it doesn't have to.
yeah OP is thinking having more transaction makes the coin more popular than bitcoin, bitcoin transaction fee is costy compare to the other coin i think that is the reason why it's more used than bitcoin, i think doge is better when it comes transaction fee and congestion happens to ethereum i guess that's because of the smart contracts.