The words "pub" and "snack" are commonly used to indicate a particular type of hostess club that specializes in Japanese folk music (Enka 演歌).
These establishments are much like a regular hostess club except that they're smaller, the hostesses are older (usually), the customers are older (usually) and the music is older.
These "pubs" are ubiquitous in Japan. There are thousands of them in Tokyo alone. They're home to the worst singing in the country.
If a pub has a Western name — it's safe to assume it's a regular pub.
Regular Japanese pubs are called izakaya. They offer food and drinks much like a Western pub.