You are correct that both ringneck snakes and red-bellied snakes are not listed as specially protected reptiles in Ontario (though this may change in the future). As such, permits are not required to possess them. It is debatable whether removing them from the wild is legal or not, depending upon the circumstances, but from a practical point of view the MNR currently seems to not worry about it.
However, both species are quite difficult to keep in captivity successfully. I have had both on several occasions, and they tend to be quite picky feeders. Northern ringnecks, unlike southerns (from the US) have a strong propensity to eat red-backed salamanders, and ignore worms, at least in captivity. Since red-backed salamanders ARE a specially protected amphibian, this would put you in the position of requiring collecting permits to catch protected species to feed to your unprotected species. I've considered applying to the MNR for this purpose myself, but have not had the time and energy to suffer the frustration involved. Suffice it to say that southern ringnecks, which in my limited experience readily take worms, are a better choice unless you have a specific purpose that requires northerns.
Red-bellies typically favour slugs, though a few do take worms in captivity. While slugs may be easy to get in the summer and fall, they are hard to find in numbers in the spring, and impossible to obtain in the winter. I tried keeping a slug colony once, and it was a dismal experience.
With all of this in mind, why would you want to keep these species? Without some particular purpose, it is hardly justified to bother trying to keep them healthy, nevermind justify removing them from the wild.
As for people breaking the law- now that you are better informed, you can at least make them aware of it!