You can't compare alcohol prices per se across jurisdictions because of diffferent tax on alcohol. However the UK is very expensive for alcohol compared to most countries (other than Iceland and Scandanavia). Its certainly more expensive to buy in the UK than the US. It doesn't suprise me that the prices are average. However, the sheer range of whisky available is amazing. Did you see the £7,500 ($15,000) bottle of 1930's whisky?
It's certainly a cool site to look at for mouth watering ideas. I was actually very surprised that Scotch imported from Scotland was cheaper here then the UK and I didn't include the Vat (not sure if they charge it for export).