Buying liquids in a duty-free shop before a connecting flight

I'm traveling from Nice, France to Las Vegas next week, with a two-hour stopover in Madrid, Spain. I'd like to purchase some alcohol (2L or less) and cigarettes in the duty-free shop in Nice, but there are a few things I'd like to know :

Can I keep the liquids I bought along with my hand luggage in Madrid ? Or will I have to find my checked luggage and put my liquids in it ?
Will the non-EU duty-free prices be available to me ?
Do I have to declare the alcohol and cigarettes I bought when arriving at Las Vegas customs ?

Best Answer

If it is a non-stop flight from Madrid to Las Vegas, then yes you can shop in duty free and carry it on the flight with you. But I am unaware of any direct flights, so am guessing you will have another stop somewhere in the USA.

If you have a stopover in the USA and if you buy duty free in Madrid, then you will need to pack the alcohol into your suitcase before you recheck your bags at the US connection city, you won't be able to carry it on the US domestic flight.

Yes, you will have to declare your purchases, as you are limited to one liter of alcohol duty free and you seem to be planning to buy more.