Having the proper koi handling supplies is a requirement for all serious hobbyists. Those who show their koi in competition know the great value of quality nets, bowls and holding tanks.
Even if you don't show your koi, having the proper equipment is very useful. Sooner or later you will need to catch and move your koi for one reason or another. Maybe it is a heath issue with one of the koi or perhaps the pond will need to be drained for repairs. It's best to have the equipment before you need it.