Maybe it's just a matter of which conferences I attend, but my impression is that "conference attendees per capita" is highest for the USA, lower for Europe, and much lower for Asia. If you want to be closest to
people in general you'd probably aim for somewhere around Nepal (mind you, it doesn't have very good connectivity for air travel); but being closest to
conference attendees is probably going to be between the USA, Europe, and Asia... in other words, Canada.
(As for the cost, when I said "cheaper" I meant in terms of the cost of conference facilities, food, and hotels. Obviously the cost of travel will depend on where someone is starting their trip.)