Canada doesn't even have free trade internally... It's literally easier to sell to the US or EU than to another province.
There are no tariffs between Canadian provinces and never have been.
Did I say there were?
I'm clarifying that the trade barriers on things like liquor and food between Canadian provinces are regulations, not tariffs.
I'm not aware of steps backwards (as in US-Canada relations) where barriers between provinces increased. Am I wrong to be optimistic?
The US has higher thresholds in every state and no federal sales tax, and buyers pay the duties.