Of course, there's always two kinds.
I'm talking about these two kinds of people: the ones that have gained self-awareness, and the ones that haven't.
Perhaps you know someone, from high school, from work, who does not seem like he (I assume a male here for ease of writing) has gained self-awareness. He knows how to make decisions for himself, he knows what's going on around him, yet he is like a zombie. He is in school because he has to be in school. He is at work because he has to be at work. He will get married because he happens to know a girl he has been going out with for a long time. Life will throw this person around and he will not even realise it. I know some of these people. These people are working at cash registers, unable to figure out what to do if a product doesn't scan. These people are programmers who, after being shown a new programming language, tell their boss that they need an official training course to learn the language, and then still cannot figure it out. Brainless zombies.
I always try to be positive about other people, but even after knowing some people for years and years they don't change. The easiest way to find out if people are zombies or real people is to have a conversation with them about life, their goals, and what they want out of life. If they haven't really thought about it, or if they can only see one path, that's a bad sign. I generally try to elicit responses from people that can only be made by humans, but sometimes people I talk to really don't pass the Turing test.
Is being a brainless zombie a problem? No it isn't. Most brainless zombies I know are perfectly happy. Probably more happy than other people I know. Still, I wouldn't want to be one.
This XKCD comic about Sheeple is quite on-topic, although I don't think it quite depicts reality. If only it did..