> I for one don't even know why there's a forgery market for ancient pottery

Because people desire owning ancient pottery and are therefore willing to pay for it.

> I for one don't even know why there's a forgery market for ancient pottery

People have paid top dollar for archeological artifacts for centuries. Humanity lost a lot of knowledge from graverobbers, illegal artifact hunting and unreported thefts of stuff getting exposed after stuff like forest fires.