First, the Commission des normes du travail won't do shit, since they a) have more important things to do and b) your suspension will be well over before they start their investigation. Not only that, but if you officially ask for an investigation, they'll show up at your workplace, contact your boss and (most probably) you'll end up on worse terms with your boss than what you would've if you just took the suspension. Most of the time employers use cases like these to serve as an example, and while you may not show up late so frequently, other employees could and it just so happened that you were the one to get fucked over.
All of this is only based on experience, since I've had trouble with an employer (Ville de Montreal) not paying me for my services, only to wait until the last day (59 days after my work was done, or 29 days after my contract was signed) to give me my check. The commission did absolutely jackshit as they only called me a month later to say they were investigating.
Also, fucking lol @ Canada's Texas, maybe Alberta or some other redneck province, but Quebec has to be the most leftwing province in the entire country (although our politicians are a complete joke with all the corruption and that way too many fuckheads are crying to keep french the #1 language)