It is exactly this sort of post that forum users should reply to because that shows lurkers that there exists a genuine level of users who get value from the product.
As for your idea about word of mouth, how many here tell all and sundry of their sub usage, very few. The vast majority come from internet searches after stumbling across the concept of subs elsewhere.
i confirm, there are many lurkers in any online business forums.
if i was the admin i would just ip ban his ass and refund his money for all the products that he purchased.
get rid of him for life, because people like this always complain and never execute