I think if they did, they’d sell less of it. Consumers would associate the cheaper price with a poorer quality product (most are probably not directly aware of the amount of duty they’re paying or even that they are). The whole goal of non alcoholic beer is to make it feel as much as a real beer as possible. A big price disparity would create more of a difference.

Not an expert, but as far as I know, the best way to make non-alcoholic drink is to make real thing and then carefully take alcohol out of it, so at least in terms of COGS the producer will spend more money. But mostly I think it is supply demand balance.