Yes, it is trivial to add 10% (or 30% for waited restaurants) to a number. Even if people did not for small purchases, with so many people living paycheck to paycheck, surely they notice an extra $50 to $150 for a TV or $3,000 for a car.

One of Amazon and other online only retailers’ biggest advantages until 2018 was that it did not have to charge sales tax to people in states without a physical Amazon presence. That meant you saved 7% or more buying from Amazon instead of locally. Basically everyone I know used to buy online to skirt sales tax.

https://en.wikipedia.org/wiki/South_Dakota_v._Wayfair,_Inc.

It was a very big deal and politicians had been complaining about waning sales tax revenues.