I don't know why hand tools couldn't be the same as, say, cars. A car is just a tool to get you from point A to point B...sometimes.
In addition, sometimes cars are collected for other reasons and never driven at all. Some are driven, but only under ideal circumstances before they're carefully cleaned and re-parked; left to be visually admired, touched, shown-off, etc. At night, the owners go to bed knowing they possess a good thing.
In my opinion, having two or more sets of tools is no different than having more than one car.