Steinways used to have no logo?

I've been told that this Steinway (I forgot the date, it's a 1920's model) used to come with no logos on it. Clearly there are Steinway emblems casted onto the iron plate, but on the cover, there's no label. The Piano and Keyboard shop I was at today is wondering if they should keep the tradition of placing no logo to keep it authentic (it came without a logo) or just go and put one on there.

If they went with a logo, it'd just be a sticker.