"The purpose of Green Zones is to better
regulate the number of campers in certain
Crown land areas, to prevent crowding, and
over-use of campsites, improve the quality of
campers’ outdoor experience and, in some
cases, distribute anglers more widely to
prevent over fishing on some waters."

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But it would be the same in the Rainy Lake district the Q is in.

I think that's a nice way of saying they don't want self-equipped non-residents from using these zones to access whatever or hunt.
I'm pretty sure you have to go thru an outfitter for certain types of game ( big), because that's how they control how much game is taken, especially by non-residents.

I think it's probably political/financial becasue the local outfitters want you to get some gear from them. I'm not sure how much "gear" you have to rent before you can get a "rate" on that Crown Land permit.
I did a little looking on-line and no matter the area/Green Zone, it looks about the same in that those Zones are set to "block" access to well established camping areas and "funnel" people toward access points that you have to have camp permits to get into and leave a vehicle.

It is confusing to say the least. I think I'd call the park in Atikokan and get the info first hand.