Because it’s the design of the product? Every product is designed with a specific usage in mind. This is designed to be wireless, hence all of the ways in which it enforces and enables that. The battery lasts a very long time, so even in your work bag it should be fine (although are you then plugging into many different computers to associate it?)

If you want a corded mouse (and it sounds like that’s a better fit), there are plenty of options on the market.