I think SA's in the US do get some sort of commission on most items. I thought I read somewhere else on TPF that they dont get commission on B's and K's but on everything else they do. Correct me if I am wrong.
TPF may earn a commission from merchant affiliate
links, including eBay, Amazon, and others
I believe in the US, SAs get commission on everything but B & K. if you look at your receipt, you will notice that all non B or K purchase has the sales associate's name attached. for B and K, commission goes into a pool and split amongst everyone (read that somewhere here).
besides commission, there is also a store/team target which, if met, results in a bonus. (I was told this).