I've had a couple of company EVs that I've charged using a 13a socket in the garage. For rural electricity supply reasons it's not possible for me to have a 7kw charger. Because of the need to use the car to answer random call outs I always needed to arrive back at home with as a minimum 50% charge, this in turn means very irritating visits to public chargers when you are nearly home. If cost is an issue you also have very limited hours at the off peak rates.
Personally unless the car is only going to be used for very short trips as well as a low annual mileage I don't think granny charging is a sensible option.
But this was about someone doing 2,000 miles per year. If you need to drive at any time and potentially do a lot of miles, you obviously don't fall into this category. For someone doing 6 miles a day on average, that's probably 1-1.5 hours of slow charging and you're back to 80/100%.
I know I'll be in the 13a socket camp doing 20 miles per day max in most cases, and some journeys of 40-50 miles. Both scenarios that mean I can charge overnight, or even during the day, to easily keep the car topped up. If I suddenly needed more, I'd pay for a home charger.
A home charger can often be set to work with variable energy tariffs, but so can a normal plug with a smart switch. I can see the best rates on Octopus Agile and set the switch to charge at the best time. With it likely being only 3 or 4kWh of energy being used each day, I don't even think it's beneficial to change to something like Octopus Go as that will mean higher rates during the day for the other 10-11kWh of consumption.
I shouldn't need to say this, but different people have different needs. Just as some people like to top up their car regularly with fuel to always have a near full tank, and others wait until they're driving on fumes. Heck, I remember growing up and people recommending never putting more than a few gallons in to save weight and improve performance - so you'd end up going to a petrol station every few days.