we already have a LOT of algorithms to choose from..some of them are very good..why in the hell we would want to just make tons of them?
o.O your Q is the same like: why the hell have sooo many different and similar operating system? Like Windows, many different versions (ok, this one is for Microsoft profit), MAC OS x, LINUX ? You can lost your self..., most of the different distros are free.., why the hell are many different, and people keep build new all the time...?
Is it enough the explanation ?
If no, then: some are for profit, some for glory, some for both, some for scam ... xD
Regards: SHNICI - Georgi