Say that only people with over $1 million net income paid income tax

Say that only people with over $1 million net income paid any income tax. Say that all states excluded food and medical expenses from a sales tax that was capped at 10%. Say that real estate tax was based on comparable sales. Say there was no inheretance (sp?) tax Say also that union labor contracts were banned.

How would all of this prevent the rich from increasing their percentage ownership of the hard assets in the world? How would this prevent the middle class from shrinking?