Pub logos often consist only of the name of the pub. This type of logo is called a wordmark. While many other businesses try to show what they do in the logo, with a pub it's just not that simple. Do you show a pint of beer? Which brand of bear? What about the lads who prefer rum? So using a wordmark for your pub logo makes a lot of sense. One exception to this is if you have a name like "The Fat Cow Pub" etc. where the name gives the designer a specific theme to work with.