As an ex-German, I initially had that same impression. "
Vhy not just display
ze full price up front!?!" (Germlish spelling added for emphasis)
Over the years, I've come to appreciate it. Sales tax being added at point of sale is a fantastic way to make taxation transparent. If I ask many of my family members in Germany what the current VAT tax rate is, they have no clue. Anyone in my city in the US can tell you exactly what rate is charged in their county as well as surrounding counties and sometimes states.
This kind of transparency holds politicians more accountable and leads to healthy competition between counties and states in the US (which is how the US was designed - the competition part, not so much the accountability part).
The other big difference (even more significant) is that VAT is NOT the same as a Sales tax. Sales tax is applied at the point where a consumer purchases the final product, nowhere else. VAT is applied at every step along the supply chain.
Sales tax and value-added tax are types of indirect tax. To compare, let’s outline the definitions, similarities, and differences between the two.
tax.thomsonreuters.com
Long story short, I prefer to do a little mental math and add 6.75% to my purchase price, to having a 20%+ VAT tax built right into the price.