The British had to come all the way to America to battle the colonist and then had to go back to Brittan to resupply all the while being attacked by the French. And if the British did get past the naval defenses they would have to fight in forest where Native Americans were king at fighting in that territory.
price of pizza increases, the demand for pizza does not change. This is because in economics we have a more precise definition of demand. Demand is NOT the quantity that people buy.