Now if only USPCC International (Canada) would start thinking about this. I think the only unique decks I've seen in Canadian Walmarts are the Bicycle Heritage Edition Playing cards and Bicycle Tragic Royalty. I honestly can imagine they moving a ton of decks with some unique decks in Canada.
The Bicycle 127th Anniversary deck was a Canada exclusive. Texan Palmetto Backs are also made for exclusive distribution in Canada.
At one point, IPCC was indeed a separate company owned by USPC and they even did their own printing. It wasn't uncommon in the past for USPC to have several cities printing decks as they acquired the companies the previously ran them, though IPCC was wholly their own creation. Over time, however, anything outside of the company HQ was shut down, all the decks are made in the greater Cincinnati area (Erlanger is a suburb of Cincinnati) and IPCC is more of a marketing outfit for USPC decks than anything else.
It's not that you'll never see some of the custom decks they distribute in the US going to Canada, but Canadian law would require packaging changes, such as labeling in French and English. Us lazy, stupid Murricans don't like that as much.
So it's not like USPC can simply dump their English-only decks in your stores. Packaging changes cost money and the Canadian market isn't as large as the US market, making it hard to justify making Canadian-mandated changes to decks that will sell mostly to Americans. Back when IPCC was still in operation as a print shop, they did their own printing and it was a non-issue to comply with what was for them the law of the land. It's not considered efficient today to scatter the company's resources rather than consolidate them in a single place.