Rrocket, what are you smoking? These are all high profit lines for each of those manufacturers. Do you really believe that Toyota spent all that money setting up a brand that meant nothing?
No..I'm saying that it's no surprise really when one of these brands outsells the other and vice versa. They are all relatively low-volume, in terms of US sales.
So is it a surprise that a lesser and cheaper brand outsells it? Let's be honest...the Buick line is NOT in the same league yet as Lexus, M-B, Audi, BMW in terms of a reputation as a true worldwide luxury car maker. It's possible someday...but the entire revamped Buick line is less that 2 years old at this point. So no, I am in no way surprised that Buick or Cadillac could outsell ANY of the luxury icons in a given month..or even a given year. I mean..think about it. There is ONE car in the entire Lexus line-up that is cheaper than any Buick. And that's the CT200h that isn't even available yet! Every other car in the line-up is more than Buick, and Lexus doesn't offer the typically large incentives/rebates and whatnot that industry leading GM does.
Even last year at this time with an incomplete line-up, Buick still outsold EVERY luxury brand except Lexus, M-B and BMW.
Heck, Lexus is the sales leader in the US for many years and they typically don't sell much more than 200,000 or so cars per year.
Average MSRP of M-B across their line (No SLS) is $72,800
Average MSRP of a BMW across their line (exclusing M cars) is $61,000
Average MSRP of a Lexus across their line (excluding LF-A and hybrids) is $60,000
Average MSRP of a Cadillac across their line is $56,000
Average MSRP of an Audi across their line (no R8) is $54,000
Average MSRP of an Infiniti across their line is $51,750
Average MSRP of an Acura across their line is $44,200
Average MSRP price of Buick across their line is $36,000
So not terribly shocking.