Counting the amount of money your customers pay you as "revenue" is not a bullshit metric.

Amazon books revenue when someone orders a product, even if that product is "fulfilled by" a different merchant behind the scenes. Some people think they shouldn't be able to count that as revenue. Intelligent accountants disagree with one another.

Accounting is hard. It's rarely black and white. Anyone who was seriously interested in buying Groupon knew what their business model was (collect X from consumer, give X/2 to merchant) and this restatement won't change anyone's informed opinion.