you don't need to. since google is interested in providing you cheap relevant clicks, it will deliver them to you without exposing all the targetings. all the data available wil be utilized in choosing the right audience anyway.
And if you do branding... branding is hard to measure anyway.
Note -- I'm not affiliated with google in any way, I just think their offering makes a lot of sense.
If you're selling a product that's available nationally and appeals to a reasonably big demographic, you might not care much about targeting.
But if your business only supplies weddings in New York, then impressions/clicks by people who aren't planning a wedding in New York are largely worthless.
If they have an Alexa device, Amazon can get shampoo manufacturers to pay to be the default choice when someone says “Alexa, order more shampoo.”