They don't refuse to educate themselves. What is there to educate themselves about? They know full well what the military is about and probably better than you, considering their life time of experience. Regardless, they don't care about whatever it is you want them to be educated about, they care about their daughter's wellbeing. They probably see you in some retarded war getting yourself killed over nothing, because they believe you have rose-coloured ideas about the army. Or they see your life being destroyed because of people in the army making you miserable, bullying you, accidentally shooting you, whatever. Don't you see? It's not prejudices about the army as such that's making them disagreeable, it's their worry for YOUR wellbeing, coupled with believing you are too young to make any such decision. And no, it's not weird that just because you did a few googles they didn't stop worrying.