said by mob: GV is not available in Canada yet
One can work around that. Get a virtual US phone number (i.e., IPKALL), a voip phone client (3CXPhone or other) for your computer or smartphone, and feed GV into that. Unless the business doesn't allow US area codes in their system, you're good to go.
Another alternative: Get a burner phone and give out that number. You can choose to turn it on or just check voicemail on a regular basis to make sure you don't miss a call you actually need to know about. It costs a few bucks but if one is that upset over being disturbed by phone calls then it's worth the outlay.