Now.... what did you say again? Oh yeah, "no canonical storyline." It's there, you just have to look. You can find ties between most of the Bomberman games, if not all.
I wouldn't call it canonical, but the connections are undeniably there. Bomberman was never a series strong on story, so I'm of the school of thought that Hudson just likes recycling characters for the sake of feigning continuity and because they're too lazy to come up with new ones. Mwaha.