Depending on what you are reloading for, it can be some cheaper or not at all. Some of the common bulk ammo out there today is cheaper than what you can reload for, generally.
However, to me it is the ability to tune a particular load for a particular gun that keeps me at it. When factory ammo gives you 2" groups at 100 yds, and you can shrink that considerably with your own home brew, now you've done something.