Why pins under weather strip S500?

I noticed that if I pull back the rubber rain guard along the top edge of any door on my 2005 S500 4-matic there are a total of 4 sets of 2 stainless steel 'pins' underneath along the roof line. Could these pins be used to mount a roof rack? I had a similar set-up with my (now expired) 1990 SAAB 9000. On that car the 'pins' were actually holes into which a Thule roof rack system fit.
 
If these pins are for a rack system, who makes it?
 
If not, why are they there?
 
Thanks for your input.