Glasses fetish is quite common, it’s definitely real because there’s a Japanese name for it Meganekko. Then again there’s a Japanese word for pretty much any fetish you can think of so maybe that’s not such a certain proof of its existence.
This guy has to be borderline. While his crimes don’t appear to have a sexual element I can’t help wondering if he hasn’t got any glasses porn tucked away somewhere. It does seem a strange compulsion to have otherwise. Or maybe he had a fixation on someone, maybe a girlfriend or a movie star even who wears glasses?
We all have our little obsessions that to others must seem incredibly strange but committing armed robberies for glasses frames is at least odd measured against most people’s view of vaguely normal behaviour.