We haven't bought it when traveling by road but I'm pretty sure my insurance from work would cover me. I'll probably look into travel insurance next time we drive (or sail) up to BC just in case.
We did buy it on our cruise to Alaska in 2012 and that turned out to be a good thing. DW managed to close her thumb in the back jamb of the bathroom door as we were leaving Ketchikan. She ended up having the nail removed, antibiotics, and at least one more visit to the medical center to have the dressing changed. Cost about $450 (on our room account!) which was covered without question by the insurance. We did have to pay up front but the reimbursement check came pretty quickly.