Pieces of games never went to waste in my house.
I have two brothers. My father has one sister, who also has three children. I used to live in West Hempstead, NY, and my aunt and uncle lived in Manhattan. Until they made aliyah - moved to Israel - when I was seven, the six of us would get together and play games during family visits. At least, when one of us wasn't crying or fighting.
We played Pit, Flinch, rummy and other six player card games, poker using fruit loops as chips (we all lost). Lots of card games meant a lot of decks with missing cards. And what do you do with piles of almost complete decks of cards?
We were the card house building champs. Even today I can still build an eight level card house and card houses that can withstand books being dropped onto them. We would cover half a room with castles and houses.
Then we took rubber bands and marbles that were left over from chinese checkers sets and marble runs. Houston, we are experiencing incoming meteors.
How about scaling cards? I never owned much in the way of baseball cards, not being a sports fan. But I spent hours practicing scaling cards against walls. I got pretty good at getting the card to lean against the far wall from one side of the room. Then I got pretty good at knocking over cards that were leaning against the wall. Pretty soon there were piles of cards littering the far wall.
We also scaled cards to knock down the card houses. This took a lot longer, but I also got pretty good at the powerhouse scaling throw. Wham.
Plastic pawns were used to populate the card houses. Money could always be cannibalized into some other game that was a few dollars short. Risk armies - well we just bought another game of Risk and had some armies to spare. Except that once, instead of the wooden pieces we got a set with awful plastic triangular spoke pieces and hexagonal spoke pieces. We hated it.
Boards that we didn't need we used for a hamster run - we only had hamsters for a short while. We also used them for obstacle courses for our car races.
We had Mattel and Hot Wheel cars. We used to have favorites. They were either the fastest, the neatest looking, the newest, or had some sort of legend build around them. I had one car "Mazda" that I always took with us when we went on trips with my parents. My brother and I would sit in the back seat, and the car would go on the ledge behind the seat. It started in the center, and would roll back and forth as the car turned. When it hit one side, that person won a point and the car got put back in the middle again. Mazda was tough. Even though the paint had almost all been scraped off, it still rolled great, unlike a lot of junky cars whose wheels broke off without much pressure.
I had one of those Fisher price parking garages, the one with three levels, an elevator ,and a ramp. When a car was put into the elevator, you cranked it up to the top level where it automatically rolled out because the floor of the elevator tipped it out. With the right cranking, it tipped the car out right onto the ramp. The car then rolled down the ramp, which did a 180, and continued rolling across a few floor tiles. If you placed a game board right after the exit to the ramp, upside down with a slight fold in it (say a 170 degree angle, held there by books), most of the cars had enough roll to jump over the bump and keep going. We would measure the distance, and whosever car had rolled the furthest won.
Other times, we would simply line up a few cars and alternate rolling dice (from defunct games, of course) for each car, moving the car a number of tiles forward according to the die roll. First to make it to the other side of the room and back was the winner. Sounds dumb now, but we did this over and over again.
We used old game boards to create walls in the course that the cars had to go around or over.
And don't get me started on Lego.
By the time I was nine, my cousins were long in Israel and I had discovered D&D.
 My own kids managed to destroy all of the cars in about a month.