[Discussion] Do Rogues not aggro Scav?

Title. I'm a level 21 noob. I was sniping Rogues when I suddenly heard a Scav right next to me. Eventually, everything aggroed, and a bunch of Rogues rushed and killed me.

​Are Rogues allied with Scavs? How did that Scav even get inside? If you play as a Player Scav, is clearing Water Treatment just free loot?