Businesses are incentivized to not include taxes in the price since there's no laws against it, everyone else does it, and it lets them advertise better prices then they actually have. Personally, the practice really irks me and my small act of rebellion is that I pay in cash if tax is included in the price and by card if it's not. I wish people cared about it more but I suppose there's just more important things to worry about

> it lets them advertise better prices then they actually have

It’s a bit more nuanced than that. The issue is that cities will often have their own sales tax, or that states have different sales tax. This gets pretty complicated when you advertise a price near the border of a tax cliff. Well, not complicated for the customer, but for the business.

It is a laughable excuse. Literally every other country figured this out. It is not like borders and taxes exist only in the US.

Luckily, in places like here in the EU, when watching Dutch TV, I don't see prices that I'd expect in Germany. When someone buys my goods from Germany, I might pay German VAT or they might pay Netherlands VAT. It depends. Point is, I don't have to think about taxes, the business handles it.

But here's the other kicker. The Netherlands VAT is ~21%, the German VAT is/was 19%. It's a pretty simple difference that's basically negligible.

In Kentucky, sales tax is 6%, but in Ohio it's 5.75%, not that big of a difference. Oh wait, in Ohio it's 0% going through the drive thru. In Tennessee, sometimes there's no sales tax on clothing.

Tax is a political tool in the US, not so much elsewhere.