To each his own. For me it's just another facet of the shooting sport with its own body of knowledge.
On the plus side, a lot of us just enjoy reloading, especially for different purposes, such as hunting vs paper punching. I've reloaded for pistol (including semis), rifle and shotgun. You can usually save a good bit of money over time...and then find an excuse to spend it on newer equipment. It's also useful for those odd calibers that you can't buy, like .357 Remington Maximum. It's now hard to get brass for this caliber.
On the minus side, it costs money (not necessarily a lot of money) to get started reloading and, like shooting, requires your full attention. Apart from potential injuries to yourself and others, the gun manufacturers' warranties typically won't be honored if they find that your firearm was damaged by a reload. I wouldn't let that deter someone from learning to reload, but it's one more reason for those who aren't interested in it.