In Australia, Maker's Mark lowered the proof a while ago. The bottle I have in my pantry is 40% (80 proof). Not to mention, bottles run ~$40 (1 AUD ~= 1 USD), so I suspect the branding/marketing considerations are different.
I rather suspect it is pure price discrimination. I saw Pabst Blue Ribbon for AU$49 a case. PBR! Sierra Nevada Pale Ale is around AU$75 a case. These prices are at a huge discount retailer (Dan Murphy's).
[1] http://theconversation.edu.au/calling-time-on-alcohol-taxati...