It should not come as a surprise that Iceland is an expensive country, but the travel company Intrepid did some research into how many beers you could buy around the world for 20AUD or about 1600ISK. Mbl.is reports this.
According to their research, the cheapest beer is to be found in Vietnam. Beer costs mere 1.35AUD there, or about 109ISK. The beer in Iceland, however, usually costs about 1200ISK or 14.50AUD
Other countries with cheap beer are Mexico, Egypt, Kenya and Burma, but there you can get beer for about 2.5AUD or 200ISK.
However, most tourists probably come to Iceland to buy a round of beer. They most likely come to the country to travel the Golden Circle and explore Icelandic nature.