When someone consider that they need to schedule their time for gambling as well then they are some kind of addiction to it, no one should ever make it as daily habit even though if they are having time limit because over time the addiction will increase and increase and will result into severe kind of addiction.
On the other hand when someone gambles occasionally they need to have a time limit so they can avoid getting exhausted.
When you have family, work, friends and some other activities, one way or another you will plan them all. This does not mean that you have some kind of addiction. In fact, this question is relevant only for a small number of people (who have an almost unlimited amount of free time), most people live in a tight schedule and a constant lack of time.