Groupon = Avant Garde with a customized 'R'

Collective Buying Power = Clarendon

The ITC-version of Avant Garde has this R.

All versions does in heavier weight, no?

That's the original Extra Bold R. Originally, only the lighter weights had the gap in the middle of the R, but when a multiple master version of AGG was done in the Nineties, the gap was forced into the bolder weights for consistency to make weight interpolation possible. Multiple masters failed in the market, but the design changes in AGG persist in certain versions.

When I read the title of this post, I started thinking "Hmm...a groupon for a fonts bundle...interesting idea!"