it's not that they necessarily need to make 100 trash instead of the 200 of each required, but who would be willing to craft cases when all you get is a rig formula that no one will craft. I have gotten many formulas such as fallen wish formula, kitten star formula, fafnir formula... those formulas that are not worth crafting bc its cheaper to buy in mp instead.
oh and alot of people are looking for certain formulas. (alchemy formulas).
I think what gaia needs to do is have those show up rare, and have more alchemy formulas show up such as ectoplasm, maybe some inizio formulas too, and other unique alchemy formulas.
supply n demand.
i have been so discouraged to craft alchemist cases lately when I always get rig formulas. who would wanna craft a case and open it when you can make 4 caches instead. It's a safer bet. Ive lost alot of gold crafting and opening cases, thats why id rather sell my formulas for around the price of an unopened case.
p.s. i support the idea of 100 of trash instead of 200 though too.