If I were a machiavellian executive at CTV or Global, I'd look into hiring a couple of dozen work-from-home staff to file ATI requests at the CBC. Pay them, say, $36,000 per year to file 50 or 100 requests each and every month - whatever's a reasonable workload.
Same thing for UPS and FEDEX with Canada Post.
I suspect it would be money well spent to completely screw up a direct competitor like that in a way that they couldn't reciprocate. Of course, you'd have to get a bean-counter to crunch the numbers, but from a hassle perspective alone, it might well be worth it.