> Because it makes state-level or national-level advertising of prices impossible. Or even local-level in many cases. In large countries like Canada, and I wou

> Because it makes state-level or national-level advertising of prices impossible. Or even local-level in many cases. In large countries like Canada, and I would imagine the US, you probably don't want to advertise prices nationally. The cost of goods to will be different for a business in Vancouver and Southern Ontario compared to the Atlantic Provinces. Never mind small towns in remote communities connected to the road network, such as Northern Ontario. Especially never mind small towns in remote communities that are not connected to the road network.