My grandparents had stashes throughout the house.
It was the way they were. We used to joke about getting to their house after they died before my mom & aunt slapped on the padlocks.
As they aged my mom & aunt took over the day to day tasks for them. After going through the house with my grandfather they took him to the bank to deposit almost $15,000. This was after the $10,000 law had been passed. :) It wasn’t confiscated.
Same thing happened to us, found cash taped to bottom of drawers, behind picture frames, in pockets of things hanging in the closets....even found cash years later in backs of books....