For the most part, this is how our system works.
The back of the ownership are two transfer documents. You, or the seller, will fill out the vehicle portion, including the mileage of the vehicle, and the seller signs it. The buyer takes that, and the seller keeps the half associated with the license plates. He can then use that to transfer those plates to another vehicle, turn them in, or sell them. You have six days from the purchase of the vehicle to do the transfer. It is absolutely not enforced, and I currently have 5 ownerships in my possession that haven't been changed, one I've had about 13 years. In most cases when you buy something the seller just signs the document and leaves the rest up to you. During the process the ownership is thrown out and a new one issued in your name.
If I buy a parts car it never goes in my name because I would have to pay the transfer fee and taxes, which could be as little as $40-$50. Wreckers don't care who's name it's in, and I've never seen one that cared if there was an ownership. Taxes are based on the wholesale value of the car, or if the car is 20 or more years old, the appraised value. I've never been asked for an appraisal, only what I paid, which is often as close to nothing as I think I can get away with. I haven't been asked for a bill of sale in probably 40 years. For bikes, because there's no values or appraisals, you and the seller agree on a selling price for the purposes of transfer and taxes. The ministry has, in the past, contacted the seller to see if the sales price agrees. If you buy a vehicle that has a signed ownership, but never been changed over, you just take the ownership in and change it over like you bought it from the original owner/person who signed it. As far as I know there's no way of them knowing.
When my FIL died we got his low mileage 78 Malibu. Obviously he couldn't sign it, so when I asked the girl at the Ministry of transportation (Now Service Ontario) what to do she said, oh, just sign it yourself, that's good enough.
We have a pretty easy going system. The only problems you typically run into is when one of the employees doesn't understand how it works. So you can either tell them how it's supposed to work and they'll take your word for it, go to a different office, or call the hotline and get the info along with a name and extension for when you go back to the office. For the most part I've had very few problems, and when you find a good office with knowledgeable people, you treat them like gold because if you find a car or a bike in a barn, a field with no paperwork, or as I mentioned earlier one selling cheap because it as "no title" they can make that process a simple 15 minute transaction.
This is the back of an ownership from something I bought three, maybe four, years ago. I will never likely put it in my name because I don't need to for what I'm using it for, but when I go to sell, an ownership will net me more money and an easier sale