Why do people like taking selfies? Well it’s human nature, we have an obsession with ourselves and this hasn't changed since the 1800s.
The only thing that changed is the technloghy and the ease of use of it. Back in the day if you wanted a picture of yourself, you paid an artist to draw you a portrait.
The portrait was a declaration, "I'm great, look at me" the subject would look perfectly possed and light. Now skip to current daytime and what do you see? We have these mobile devices that we can have a portrait of ourselves in a matter of seconds and like our ancestors. We only want to be pictured in the best light.
Technology is advancing but humans aren't, we still have the same nature and care about the same things. Technology just enables are ego and deviants self from the comfort of anywhere.
When I see people taking selfies, I don't pay much attention to it, because in the past houses were full of portraits of themselves.