My understanding is that if you're not a US resident you don't have to pay US sales tax. Same applies in the big stores in the UK. If you're not a resident of the European union you get the VAT (Value Added Tax - 17.5% ouch) off. VAT is applied on everything except children's clothes and food. Always worth asking. Some stores ask for a minimum spend of £50 in the UK.
Not exactly. The UK has VAT, the US does not. The US has a sales tax that is collected by the local state, not the federal government (that's why they don't charge the tax if you have it shipped out of state). Everyone pays this tax regardless of if they're American or not, and you can't claim it back at the airport like you can claim back VAT in the UK.
I'm pretty sure this discount from Saks, Bloomingdale's, etc. is a true discount, not any form of tax refund.
I think it works like this in Canada too, but I'm not 100% sure since I haven't been there.
The 11% discount at Macy's does not include everything. It did NOT work at Louis Vuitton or any of the cosmetic counters. My fiance used it for some sports apparel to work out and was happy though! (& p.s we're canadian)