It is a question of cognitive load. If you turn wifi off and on you need to _remember_ to turn it on when you are in an "I want to use wifi" zone. If you forget

It is a question of cognitive load. If you turn wifi off and on you need to _remember_ to turn it on when you are in an "I want to use wifi" zone. If you forget then you end up using your data plan. You could use a geofencing app to handle turning wifi on/off (say at home and work, etc) but then you are just trading battery issues. Additionally, at least on android, wifi scanning improves location services. At least for me those are important, specifically when I am not at home or the office.