I did actually did get a skyteam branded card once which invited me to enter the "Customer Experience Survey", this was on my flight in J with Aeroflot from Moscow to Hong Kong in 2014. No unique code needed and I could win 2 round trip tickets to a Skyteam destination of my choice (did not win). Card was both in English and Russian. I had to log on
http://www.skyteam.com/yourfeedback