BBs can easily lower staff prices just by creating more staff. I wonder why they don't do this?
I can only assume they want to limit the amount of teams that have access to top level trainers. I wouldn't have an issue with that, but that could be what led to assumption.
For me, "supply and demand" is more a case of "we all have a massive supply of money and we all demand the best". Div4 teams shouldn't have access to the luxuries that div1 teams should (Disclaimer: I am in the lowest division in my country). If you want access to things like level 7 trainers so you can train a world class player, you should have to earn that, not just tank and daytrade a financial security net.
That is why I believe making the hoarding limit divisional is a key strategy to reduce inflation. Flood the market with ready made players, not only to remove money from the economy, but to force salaries that can't be sustainable by wealthy teams in lower divisions, making it necessary to seek promotion. Once teams balance their finances to suit their level, you lose the situation where everyone is capable of having everything.
It will be another 6-7 seasons before I have a reason to promote in the current system, and I'll have 25 million reasons to not care how inflated the economy is.