I don't travel internationally to perform -- one can only wish -- but I do cross borders a good deal for business, including Canada's. It does help to be representing a well-heeled multinational with lots of lawyers, but I must say Canada is a real pain in the arse to get into. Even if I am going to one of our own company's offices I have to demonstrate no possibility that I might do work a Canadian could do. And I can't bring anything that looks like even a *picture* of a tool or test instrument with me.
(No offense personally to any of you, unless you work for the Canadian immigration service.)
But lots of other nations require either proof of a return ticket (for a very short-term work visa only) or a cash bond equal to the value of a return ticket. So if they have to shove your butt out it will be at your own expense.
The officious handling of these sorts of things is never a surprise. The Vogons are closer aboard than you think.