Do the smaller limestones from excavation get reused? Whether it be from a home foundation or an entire shopping mall. What happens to the non-modular ones?

Hi, I see they obviously keep large modular stones to sell for retaining walls. However, there are plenty of slate-like to small boulder (300lbs>) that I wanted to know what they get used for.

If any home builders or excavation/dirt moving contractors could chime in, I’d love to hear the process of sorting.

I am building a landscaping business and these would be useful to dry stack or even use in my gardens. Thanks