Seriously.
I mean the energy some of these folks put into trying to trash this dude, I don't even have enough to read through let alone write, is telling about your character.
Anyhow, regardless of his intentions for amassing gil, there is a lot of gil in the system and I can't help but wonder how storing it will not eventually become a problem. The standard subscription allows for two retainers, so having more than 3 billion (not counting FC chest) will cost additional fees. While probably not currently a widespread problem, 3 billion is not an inconceivable amount for dedicated crafters to hit.
Inflation is real, hell I remember when I had 16 m and I thought that was an infinite amount, took a couple years off and came back to find out I was broke. To be honest though, its hard to imagine SE wanting to increase the gil cap with RMT and all, but they seem to be doing just fine without it so you never know.