The things you are mentioning that wealthy people are buying are not actually included in the Consumer Price Index(CPI). The CPI does not include real estate, stocks, bonds, or any other investment items. Yes these assets have all appreciated in value greatly in the past year but they do not affect the CPI as they are not considered day to day consumption expenses.
Secondly, an important point to keep in mind is that we actually are aiming to have a healthy amount of inflation. A lack of inflation or even worse, deflation will cause negative effects across our economy.