Fishing in the city

I see this from the train on the way to work each day and I have yet to understand the appeal of fishing in what are effectively outdoor swimming pools. OK, so you might be guaranteed a catch, but where's the challenge? I've never been in to fishing, but had always assumed that the appeal came from a mix of being close to nature, the thrill of the chase and also the slow pace. Sitting by one of these pools in Ichigaya you have little of any of that as you have a main road on one side and the Sobu Line on the other.