We even have a regional word from that: “Entenklemmer”, which translates verbatim to “duck pincher”.

Some folks when leaving their ducks out of the enclosure, they’d check each duck for an egg in said pipeline. If there was one, they wouldn’t let that duck out, because well, they wanted that egg.

So, an Entenklemmer is a scrooge, someone going to great lengths to not miss out on even tiny profits.