adding to the pile 

The act of taking a massive dump inside a toilet that is already clogged with a massive dump that someone else previously took.

“Hey, Jack did you unclog the toilet?”

“Nah, dawg I was just adding to the pile!”

adding to the pile by Trident of Treason October 2, 2018

Adding pennies to the pile 

Adding or contributing a small (usually unnecessary) bit extra.

When John decided to help out the cleaning by taking away his rubbish from lunch, he was just adding pennies to the pile.

Adding pennies to the pile by Fred Invisible October 24, 2010