I appreciate your explanation. Let's go with your numbers, and say 90% of likes are bots, while 10% are real. You're getting much less value from your ad spend than you would if 100% of the likes were real, but so is everyone else who's running ads.

Meanwhile, the 10% real people have friends who could potentially like your brand organically as they see it in their feed. These second-degree-of-separation people, who have not seen your ad, will first be exposed to your brand through their friends' likes. You're building mindshare, however minor. In the small chance they decide to check out your page, having a believable number of likes already on your page is beneficial in winning their attention -- and interaction. The post that talks about 'bootstrapping' your likes with SE Asian users who are more like-prone to entice the Japanese/Korean likes is making the same point.

There is no doubt that bot-likes are much less useful than real-person likes, but they're not useless.