Most people don't start shopping at grey/black markets in order to avoid paying sales tax. Most people don't pay their employees under the table to avoid paying

Most people don't start shopping at grey/black markets in order to avoid paying sales tax. Most people don't pay their employees under the table to avoid paying income tax. Most people don't move or de-value their own homes in order to avoid paying income tax. Those taxes make up most tax revenue, and wouldn't get caught in that definition.