In Chicago area for anyone wondering using the Walmart charging network. This is about ~13% capacity, wasn't really low started charging at about 70%.
The people with charging at home that I know are paying an effective rate close to 0, due to smart electricity contracts where they get time of use rates at a 15 minute resolution. Then they set the car up to charge when the price is basically nothing, typically during night. It's even possible to get paid to charge when there's excess capacity in the network.