Just wanted to add my 2 cents here.

Like Hermes, the Airport Boutique store at FRA (which is in the public area) which sells Rimowa products without the LH logo does it the right way where they give you the regular customs form to be stamped and then you go back to the store and they process the full VAT amount back to your credit card (Hermes after security gives you the VAT in cash back on the spot after you go stamp the form).

The customs officer told me that it's the store's choice whether to do it this way or the Global Blue way. I bought something at Boggi in the public area and they use Global Blue which takes 1/3 of the VAT for them. What a ripoff. I had no time or desire to try to figure out whether I could somehow force them to not use Global Blue, especially in light of what the officer said.

By the way, the number of receipts that visitors from China present for stamping is a sight to behold. If you're planning on getting forms stamped or getting your money from Global Blue (two separate lines), make sure you budget significant extra time (as in 30-60 minutes) for this. There may be no line or it could be crazy. Maybe see if there are flights leaving to China around your time. No joke.

So ^ for Hermes and Airport Boutique and for Boggi and Worldshop.