I guess that’s just for hard alcohol? Iceland has beer in tourist shops at least, if not grocery stores. But in tourist shops it’s expensive enough that you wouldn’t want to stock up there. I saw individual bottles for $10 (cheap beer) and $20 US (nice beer), for example, at the Gullfoss store.
Iceland does not have beer in tourist shops or grocery stores. Alcohol is only sold at the state run monopoly, bars and restaurants. What they sell at grocery stores and tourist shops is non alcoholic or with a very low (<2.25%) alcohol content, and they're mostly produced to circumvent the ban on alcohol advertising.