Yes you would not, because as I said, they are not in loot tables except for loot bags so chance to get them is one in a milion. Thats what I was pointing out. I suppose that is a bug?
You are right that visibility outside once moon comes out is more then sufficient to aim at zombies. I was however thinking more in terms of clearing PoIs.
Sneak bonus is awesome, but as you mentioned, you need silenced weapon to be effective. Not long ago I argued that they are hard to come by on which you replied that is by design, because AGI has more weapons. So if you want to spec into AGI from the get go, you are rolling dice where odds are largely stacked against you. This is issue n. 1. Large barrier for entry compared to other specs
Yes, you can get perks from other trees, but with other trees you need only one combat perk to use them, whereas in AGI for stealth you need 3 - bows/crosbows or pistols provided you found silencer, stealth dmg and stealth effectiveness. This means less perks to put into other trees if you wanted to be effective in combat. This combined with the fact that AGI has no gathering perk is issue number 2. AGI build is weaker compared to other trees.
My idea of stealth build was to get muffled military armor, silenced weapon and night vision goggles and go clearing PoIs at night (which I presumed was what night stalker perks are for). I always counted this as one of the benefits of AGI build - ability to clear PoIs at night. I thought that is pretty cool, but I guess that was never the intention from your statements "Who uses night vision goggles? Those are dumb gimmick" and "I'm talking about hunting zeds outside at night, not clearing POIs at night."