rich people investing all money in land and metals?

ok ive been wondering this for a while. Do you think it would be wise (if you were rich, making millions a year) to instead of putting all your money in the bank, to instead put that money towards physical investments, such as land, and precious metals, like gold, silver, and copper, and whenever you need some money, sell some of it, have like $600,000 in the bank, and like $10m in metals and land, that way you wont suffer from inflation and all that, while still gaining money from the increasing value of the metals and land