Hmm while I admire your openness and goodwill, and feel bad for your loss, generally a FC chest is only stocked to the lowest average wealth level of the FC. It means it shouldn't be stocked with stacks of things worth over hundreds of thousands each, unless the wealth of vast majority of people in the FC is hundreds of millions. Anything that is serious enough to actually warrant consideration should be asked for, traded and used with supervision from real people only.

In my opinion, the FC chest is too small anyways to stock with all the possible items for levelling a crafter. Most of those items are buyable too, or acquirable on short notice if someone asked, no point in stockpiling in in the public FC chest. The FC chest should be used for quick-access items such as chocobo feed, gardening, materia, glamour, etc. Which are never so expensive they would warrant consideration for security. Or handouts for FC events, which are meant to be taken anyways.

The gil count is also not for stockpiling gil, it's only filled up by the master when there's a project, aka buying a new house. Otherwise everyone's gil are their own and better to have it in your inventory and usable, than sitting in a chest. Same logic with most items. Better have it in your inventory and used, than sitting in a chest depreciating and unused, until someone decides to rectify that, and clears out the chest.