I’ve discussed Loopring fees with the @loopring account on Twitter. Loopring does have a subgraph (https://thegraph.com/hosted-service/subgraph/loopring/loopring), however it’s not currently in a position to provide aggregate fee data, as mentioned by @loopring:
Getting the total ‘transaction fees paid’ from our subgraph (which includes many different tokens) might not be so straightforward. We also haven’t implemented the $USD derivation yet on our subgraph so we’re using Uniswap’s API to get these figures on our block explorer in the meantime
I’m in discussion with the team about the potential of updating this subgraph.