better discounts available
I have SIXT GOLD. Whenever I go to book a car in Germany I find the rate HIGHER than the normal "internet rate" for US travelers if I enter my Gold number.
Try it - go to book a car saying you live in the US and get a rate.
Then log in with your GOLD number and do the same.
Rate is HIGHER because the discount is off the standard rate and the internet rate is even cheaper than that.