Not so sure the market forces are at work with petrol...

Not so sure the market forces are at work with petrol prices.
opec say it has nothing to do with them and that any additional supply would not cure the problem.In a recent interview one of the top exporters blames speculators, not oil companies or producers.There are a lot of millionaires being made at the moment.

My question is gst and how it is charged at the bowser.
If the oil company sells it for $1.0 a litre to the local servo,he puts on his margin with gst on top of that.
If he pays $1.20 then gst goes up proportionlly yes/no ?

If this is the case the goverment is making more as the base price pre gst goes up