Even if I chose to never start Dawnguard quests?

Yep.

And they will infuriatingly kill perishable low-level unique NPCs, who decide to come at the hostile boss-level vampires that get dropped into town instead of run for cover.

Kiss Adrianne Avenicci goodbye.

Only starting at level 8.

Interestingly, in 100 hours I've only ever had 2 vampire attacks, and nobody died.

Might be because I never fast travel, however.

Damn. Maybe I shouldn't install it.

I like taking my time with DLC so I can make it last but I'll have to hurry and finish these main quests for dawnguard to prevent attacks. Attacks or not, I'm still installing this one.