Though I understand the reasoning behind such complaints, I would argue that a broader geographic space should (a) improve the ability of a host city to absorb a larger volume of visitors without causing congestion and (b) give visitors a greater variety of things to do and see during their stay.
Does someone from host city A have a long-standing friendship with a site selection committee member for event B, and if so, is that relationship strong enough to usurp the economic, financial, and logistical considerations raised above?