What is double taxation (2)

The only (meaningful) double taxation scenarios that I can think about are 2:

1. You own a business that makes money. Then when the profit is distributed to you, you pay income tax. That is double taxation. But in RE, you can choose to use pass-through LLC to avoid this situation.

2. You earn your income that you need to pay tax. Then when you buy things, you pay sales tax. This is double taxation, but it's how the system is set up. Ultimately, somebody has to pay for all the roads, government like fire station and police station, and school. Income tax, sales tax, coorporate tax and property tax, as I think, are the main revenue to pay all these services.

Please correct if I'm wrong on this.
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