margarinal returns
"Bare-bones" proceeds/rewards that are of far less value/usefulness than whatever it was that you originally invested into said venture... in other words, it's like you put fresh pure premium dairy-butter into da mix, and only got stale margarine back out for all your sweat 'n' toil.
I diligently updated my profile and paid my dues to a local dating-service in the hopes of scoring some sweet fresh "milk", but all I got was a bony plain-Jane past-middle-aged biddy wif A-cups and a hairy snatch dat smelled funny --- talk about margarinal returns!