it's easily verifiable, spoof your h/w,s/w and connection and visit a webpage you just viewed. the prices will be different.
there are even use cases of buying return tickets from the destination country being cheaper than buying it from where you are. it's such common knowledge that even popular youtubers are making videos about it - https://www.youtube.com/watch?v=Utsnt6GFrKo (linus tech tips-6 minute watch)
VPNs are quickly becoming compulsory tools to save mucho dinero
http://business.time.com/2012/06/26/orbitz-shows-higher-pric...