There will always be some abuse of services. It just turns out to be negligible most of the time. The benefits will far outweigh the losses. Also - people shop for services all the time. If they want to move to a province that has better benefits, that would be normal and smart. If the program ends up being mostly federal, this won’t be as much of an issue as things will be more standardized, though.
The sad truth is that the likely result of carbon reduction technologies will be an increase in carbon production since companies will say that it’s ok since we have better reduction strategies.
We need to change as humans to actually solve this problem.