Prince Rupert is really just a stop they make in order to comply with cabotage laws for foreign-flagged ships. The ship has to stop at a foreign port before returning to the U.S.
I was in Prince Rupert a couple years ago. It is a small town. I didn't see taxis but then I wasn't looking for them. We did a whale tour and it was just a short walk for us from the ship to the tour boat. However I just looked and there is a taxi company there. I was looking HERE