For one, it could be useful in earning Bulk and Skull's help to find out who's been turned into a monster.
For another, it could give us an idea of who to follow, since this person can't be killed and knows who some townies are for certain.
I didn't say we "need" to know who Zordon is. I said it would be helpful to know, and now I've supplied a few simple reasons. If knowing who Zordon is means we pull neutral detectives to our side (Zordon can trade Power Ranger info for investigation info), then why not do it?
We lose the ability for Zordon to make new power rangers if he get hit, right? What's not to say that wouldn't happen anyway, and what's to say the first power rangers are going to be killed?
I didn't say