Canada definitely had (has?) organized crime in that era, although maybe not to the extent the US did. Check out the Papalias[1] (my great great uncle was a quasi-crooked cop on their payroll), as well as the Musitanos and Luppinos, for a couple southern-Ontario examples. There’s still a (relatively) small but fairly influential Italian mafia presence in a lot of smaller southern Ontario cities, and at least a few of the Papalias are still living off of family money (my family’s cottage, ironically not the side with the crooked great great uncle, is next door to one of the Papalia’s cottages).
Hamilton is the way it is today in large part due to the mob activity from the 40s-90s.
If something happens to a lesser extent and what does happen has a lot of the consequences spill over into the US, it's not that surprising that the backlash is more severe in the US.