If one sets up Tiered Pricing for regular customers only and leave Tiered Pricing empty for B2B customers, these tiered prices will show up at the B2B customers as well, whereas only guest users and B2C users should see them.
As you can see in attached image, this pricing makes no sence in this case as the B2B price is already lower to begin with than the tiered prices.
As soon as tiered pricing has been setup for the B2B customers as well, it will show the correct tiered prices. But in my case I don't want to setup Tiered Pricing for B2B customers for some of my products.
P.S. As I would like to have Tiered pricing for registered B2C customers only as well, it would be nice to have price fileds for the B2C group as well on the Product edit page. (As I already mentioned in a different ticket as well)