Interesting twist. Castrol oils are currently on sale at Canadian Tire. All grades, except 0w-30 and I think 5w-20, but I might be wrong. So does this mean that we boosted GC sales enough for them to justify this exemption? Oh well...
The fun here is at AutoZone, you never know the price until it's scanned. Even the employees don't know if it's on sale or not. Scored most of mine at $3.99 U.S.