Ok, but where does the actual money come from? If I bought 10k of ethereum at one point in time and sold if for 100k, I put 10k into a pot which I took 100k ou

Ok, but where does the actual money come from? If I bought 10k of ethereum at one point in time and sold if for 100k, I put 10k into a pot which I took 100k out of. Basic math tells me there won't be a "rising tide" for the boats that are left when anyone else pulls out.