I got an offer for Amazon Vancouver, but I eventually want to work in the US. Is it possible to get a return for Seattle or something?
Yes
Just put your preferred location as Seattle and you will be put there. Other locations are hard enough for people already in the US.
do they give some sort of survey when giving return offers?
Yeah. You'll get to pick your top 3 locations. In reality, if Seattle appears anywhere (or if they can find any other reason to) then you'll get put there. If you really want to come to the US, put Seattle first and then 2 other major US locations after that.
Good choice, US pay is much higher for same job
yes, but im worried amazon wont let me even make that choice
Take the offer then relocate.