Just finished watching a Terminator movie and noticed that many movies display scenes in which drinking establishments have pool tables.
Thus I ask the question: Why are pool tables so popular in drinking establishments?
Billiards is one of several games that are popular in drinking establishments, also including darts, shuffleboard, and cornhole (if there is an outdoor area). These games all have some common features that pair them well with bars. They are casual in nature, short in duration, can be played 1v1 or in teams, don't require much space or specialized equipment, and require minimal maintenance/upkeep on the part of the establishment.
Games like this, of which billiards is probably the most popular, enhance the experience of patrons and help further the convivial atmosphere bars thrive on.