I grant all your objections are true, but, I can see no alternative.
Part of my plan into which I did not expand would be a market for spare
fuel ration. This could be done through the rationing computer.
Someone like me that uses a quite small amount of fuel a year could
place my excess litres onto the rationing market for the highest bidder.

Of course there will be fiddles, people buying wrecks just to get the
owners entitlement etc. However comparison with the states car
registory could stop a lot of that.
Nothing will be perfect but it might stop or reduce armed holdups for
petrol. The crux of the matter is the economy cannot survive with the
cost of fuel being allowed to reach astronomic levels.
The crude price rise will be bad enough without having on top of that
rises caused by a scramble to corner the petrol diesel market.
Re farmers, if they can grow their own good luck to them.
So long as they don't have to put more energy in than they can take out.

Imagine walking past a service station and see the $6M man filling his Rolls Royce.
You would not be a happy camper would you ?
That is what the government will have to face.
The public will demand a ration, just like we had in war time.

It is a bit like banning tobacco, sure some people will grow it but
the health of the community would be better anyway.

The problem is that the ration would gradually diminish to zero any way, even if you could afford to buy it.
Face it unless “they” come up with a brilliant new source of fuel to replace common old petrol, we will all be on bikes or horses.
But do not despair, with the latest report from the International Energy Agency that global temps will rise by 3.5C by the year 2050. There will not be enough of us left to use up what we have.

*Part of my plan into which I did not expand would be a market for spare
fuel ration.*

Ah Bazz, but that would mean that money being taxed. I betcha that
the cash fuel market would boom! All those on pensions etc, able
to make a bit on the side. Ration things, a black market will
develop.

*Nothing will be perfect but it might stop or reduce armed holdups for
petrol.*

Bazz, that happens now for money. I can't see it being any different,
wether petrol is rationed or not.

*The crux of the matter is the economy cannot survive with the
cost of fuel being allowed to reach astronomic levels.*

Ah, but high prices drive innovation and efficient use! So the
economy will change and adapt. My wheat might be used to generate
ethanol or it might be exported for food. Only the market can sort
that out.

*Imagine walking past a service station and see the $6M man filling his Rolls Royce.*

Well he might want to buy the black market ethanol that I have
just produced from my wheat :)

*It is a bit like banning tobacco*

No its not Bazz, cause right now people can freely buy tobacco.
If they banned it, like dope, the illegal market would become
enormous. Dope is one of the largest cash crops in many American
states.

Bazz, look at it this way:

The 6 million $ man can right now as we speak, write out a cheque
for a Tesla sports car. He can fill it up at home off the
electricity grid and drive around all he wants, without ever
worrying about your rationing system.

Will that upset you too? There are just so many variables in
the energy game, that it is impossible to ration and regulate.
So market regulation will make perfect sense.

Well Yabby, ultimately we are all dead.
There is already legislation to control supplies of fuel, but it is
only designed for short term disruptions. It also does not get down to
the final user of the fuel.

I just don't see how we can let say a Meals on Wheels driver go without
fuel so that someone with plenty of money drive.
I just don't believe that the government has no social responsibility
in such an emergency and can just leave it to the market.

After all the roll of the "market" in a time of zero growth or indeed
contraction is ending.
Everything is being turned on its head, most of the old principles
will be modified to their very local versions and will need
different approaches.
After all, it is quite different to take advantage of someone who
lives on the other side of a city to someone who lives at the other
end of your street.

Whatever the problems with rationing it will be needed and it did work
during the war despite the black market as people horded their
entitlements.
There was no way my father would have sold his ration coupons.