(– by hustler #5243 –)
16 Mile Creek is an important waterway, and a headwater to Lake Ontario. 4x4s tend to leak oil and suspend sediment in the water and that all washes downstream. Crown land or not the water is what's being protected – gas and oil can dilute 10 000:1 and still be detectable in a water test.
Additionally, that's in an urban area (Oakville) where there tend to be a lot of other less motorized trail users. Can you imagine the liability associated with driving there? Do you think you're insured if you're in there?
There are lots of trails south of Toronto, but they are in America.