In Ontario (at least pre-Ford) you can get full-time benefits as an hourly worker, as long as you work 40h a week or more (or maybe 35?). It's been awhile though so I'm not super confident on the details here.
Yeah, this is why, like so many other things involving regulation, there should be a gradual proportional phase-out, not a hard line in the sand. So rather than paying two people to do 20 hours each and pay for no benefits, if you did that, you'd be paying for half benefits for each, at which point you may as well just have one person doing 40 hours a week who's fully employed and getting full benefits like you should've been doing all along.
The same is true (at least in my experience) in America. Over 40 hrs/week means the employer has to pay out extra benefits. This is also why employers do not want you to work over 39 hours if you're not salaried.
In the US, over 40 hours simply means 1.5x your regular payrate after the 40th hour, if you're "non exempt", i.e. hourly. Some employers might offer something more.
