It's quite simple: with an e-car and an average daily mileage of 30 km, you need about 5 kWh of electricity. Per day. With a 2 kW fan heater running 24 hours, on the other hand, it's about 50. So a factor of 10. And the wall boxes with 22 kW and those in public areas can be remotely controlled by the grid operator, i.e. switched off. Same with heat pumps. All that is not possible with fan heaters and Schuko sockets...
Well, if you add up such nonsense, then it becomes a problem.
A fan heater does not run 24 hours a day...
A heat pump can only be remotely controlled if I buy the cheap heating electricity.
If I have the normal tariff, the utility company cannot switch off the heat pump (!!).