Oh well, if you take a closer look, you will find why: most if not all of those with surnames look weird in English are immigrants or descendants of immigrants from a non-English speaking background. When they/their ancestors arrived, they most likely do not speak English at all or might be a couple of words, some of them might not even have a surname. When they arrived at the customs, they for sure needed something English on their papers. It would make sense to take what ever came to their mind at that moment as their surname.
Such things can be observed in every English speaking countries I would say. As those surnames were actually picked randomly, and when they/their descendants moved again, they most likely carried that randomly chosen surname with them. And now it becomes quirks that lots of surnames of different spellings are actually exactly the same in their origin. Lots of descendants of immigrants no longer neither can read or write in their own language but English, some might be either able to read or write but hardly anyone can do both.