Aren't you aware that all currencies are sold on exchanges?
Also, pizza may not be sold on exchanges, but corn, soybeans, soy products, wheat, pork, cattle, butter, milk, cocoa, coffee, cotton, orange juice, sugar, crude oil, heating oil, diesel, refined petroleum products, gasoline, electric power, coal, natural gas, copper, aluminium, lead, zinc, nickel, tin, steel, gold, silver, platinum, and palladium are.
Not comparable.
We are talking about Bitcoin, not petrol or gold or pizzas.
Bitcoin can be used as a currency, as a share and as a commodity so, taing this into account, a price criteria only based on exchanges are wrong, of course you have to take exchanges into account , but not as the only way to measure. There's another 90% of activity outside to measure