It's so easy to make one, does it make sense? But think about it, Bitcoin and Litecoin are the same thing.
We have too many Altcoins! Definitely. It's purely a question of adoption. A commodity or currency will only be successful if people agree that it's valuable and they can be sure to trade it for other things in the future. I guess 99% of those altcoins won't transfer any real wealth in the future. They're interesting when it comes to new ideas, though...