I usually have enough lather for the neighbourhood... I have so many bloody soaps/creams that it'll take me years to get through them all. Most are cheap so I'm not concerned. I even usually over lather MdC but not because I try.
I don't waste soap, but I don't go out of my way to scrimp either... everything is pretty much dialed in now so that I make the right amount of lather each time.
I can make a stick of Arko last about a year without even trying