Yes, but the reason these brands weren't doing this before Gilt was because they were afraid selling excess inventory at a discount would associate their goods

Yes, but the reason these brands weren't doing this before Gilt was because they were afraid selling excess inventory at a discount would associate their goods with that lower price-point. Gilt gets around this by maintaining a semi-private space and having one-day sales. Groupon isn't private, but it's time-constrained in the same way and for the same reason. If I know a sale is on for one day only, I'm going to understand that the deal doesn't represent the every-day price. Besides, we're in the middle of a huge recession. Damn straight people are price sensitive!