It appears that's due to the SortOrder. Here's what the object for STEEM looks like:
"STEEM":{"Id":"20333","Url":"/coins/steem/overview","ImageUrl":"/media/350907/steem.png","Name":"STEEM","CoinName":"Steem","FullName":"Steem (STEEM)","Algorithm":"N/A","ProofType":"Pow","FullyPremined":"1","TotalCoinSupply":"99692126","TotalCoinsMined":"99692126","PreMinedValue":"N/A","TotalCoinsFreeFloat":"N/A","SortOrder":"526"}
You'll see it has a SortOrder of 526, which seems a little high to me. It's likely a little biased, given it's based on:
The order we rank the coin inside our internal system
I could likely run the coinmarketcap API and sort by the true market cap rankings though if people would find that useful.