Aeroplan (the company that provides the frequent flyer program for Air Canada) announced yesterday that in order to earn status with them, you must fly a minimum of 10,000 Status flight miles or 5 status flight segments. Some bloggers are questioning why Air Canada would institute such a requirement on their generous program, but I can see two reasons for this.
First, there are many people who use Air Canada status to gain lounge access, since it only requires 35,000 miles to earn. Thus someone who is a heavy flyer in the US will earn enough miles (or segments) to qualify at the highest level and then divert the earning for just enough flights to earn status on Air Canada to get free access to lounges while in the US. This costs Aeroplan money, as they have to pay the other airlines for providing lounge access, even though they do not really get any money from these passengers. If you look at their partner page, you will find that their partners are for the most part Canadian, and so these members who never fly Air Canada are also not taking advantage of the other partner earning, which is where they really make their money on the program.
The second possible reason is taxes. Canada is fairly protectionist, in addition to having a high tax structure. Thus, it is very easy for them to have to pay higher taxes on the income of miles from other countries, and since there is a large number of members that do not do any travel on Air Canada, they were earning even less on the flight miles than they are of regular members.
What is interesting in all of this is that Air Canada Top Tier members (that's how they brand their elite program) are largely in favor of the change, as it has no impact on those that fly Air Canada.