It's been many years (mid-70s) since I worked for the multi-brand retail store that sold Hammond, Steinway, Kimball Pianos/Organs, Sohmer and Everett Pianos. In the 70's we always posted a price tag that listed suggested list price, but rarely did we sell at list price unless it was Steinway.
As I recall Steinway was sold at list price, they really discouraged discounting and a dealer could lose the franchise if they did, that's not to say if the customer had a trade you could really allow a large trade in value for the piano they were trading in.
Hammond, Kimball, Sohmer and Everett were what were called "B" items which translated to the sales people as being an item that could be discounted at 20% off. "B" also told us that the owner of the store paid a wholesale price of 60% of what retail price was.
Actually overhere in Europe, Yamaha addapted to the Steinway pollicy... you are not allowed to advertise (or even sell under the minimum yamaha price). But there is a reason behind this, Yamaha relies heavilly on the dealers for their customer support... this way, they keep internet sales from pricefighters that do not offer any support, from dominating the market and so they allow people to choose their dealers based on support and not on price..