ROI of the largest LN hubs is 0.011%/year
The 20 LNBIG Lightning Network nodes have processed 80k payments and collected 5.74 USD in fees in the last month. Extrapolating, thats $68.88 per year
https://bit.ly/2G50frh
Nobody uses LN yet, this will change when people will use it
You obviously don't understand how the LN works. With more users it'll have to have more coins locked.
