The threshold for potential instant noise-induced hearing loss is 120 dB SPL at the ear. A rifle can exceed 170 dB SPL at a distance of one meter. When you're shooting a rifle, it's going to be cradled firmly against the shoulder -- a lot closer than 1 meter. Even the lowly .22lr fired from a handgun can exceed 160 dB SPL. A suppressor can knock that down about 30 dB. 130 dB is still a lot, but it's out of the 'will-immedately-and-permanently-damage-your-hearing' range at least, and makes further hearing protection (earmuffs, earplugs) that much more effective.
tl;dr - A suppressor is safety equipment.
In general, if people are shooting outside in my neighborhood, I'd rather be woken up. That's not the type of thing that should go unnoticed. And I live in the middle of San Franciso where I've watched people get shot and killed.
I'm tired of being woken up way too early in the morning by gunshots. Waterfowl season started last weekend, so it was shotguns going off a mile away. Rifle season for deer starts soon (it's bowhunting season now), and that will bring its own set of loud noises from even closer.
I'm all for suppressors, if only so I can sleep past 5AM without having to keep my windows closed.
Out in the suburbs, or further out on the edge of the city where things start to get rural, if someone has a big enough backyard that they can safely fire a .22, I'd rather they use a suppressor. It's not a case of not being woken or not by the danger of violence in the neighborhood, it's a case of neighborly manners. It's more similar to me not running a guitar amplifier after 9pm. Nobody likes to be disrupted by loud noises when they don't need to be.