I see no problem with preventing foreign buying if those buyers neither live in the homes themselves or rent them out, but that cannot extend to people who DO live in Canada.  Foreign owned properties can be an important source of rental accomodation for people who can't or don't want to buy.  At that point they would need to file a Canadian income tax return, so the lack of it would put the onus on them to prove that they actually live there for at least part of the year.