I understand... But in the eyes of the law, Griddy
is your power company, and their equipment shutting off your supply might break a lot of laws about disconnecting people without giving the requisite notice, legal procedure, etc.
Where do you draw the line? "Griddy, please turn my power off if the price goes above $1/kwh"... "Griddy, please turn the power off if I forget to pay the bill.", "Griddy, I'll take a $10/month discount if the power gets turned off when my bill is paid late?", "Griddy, I want to use non-ripoff plan, so I'm happy for you to turn my power off the minute I pay late".
See how it isn't really feasible to stop power companies forcibly illegally disconnecting debtors if you allow a debtor to agree to be disconnected voluntarily?