[hm10]

Apart from getting inspired (like other replies have mentioned), there is plenty of insight to be obtained from watching sports. It is quite fun to observe and analyze the strategy and technical aspects of a sport - especially a sport that you play and train yourself. If someone never partakes in that sport, then yes - they may not necessarily understand the subtleties that happen in a particular move. But even if you're a hobby player, watching top pro athletes or teams utilize the techniques you are learning can make you appreciate the amount of work, skill, practice, and determination that goes into it. And that can be useful for people to apply in other areas of their lives.