I think vacation is incredibly important! I work in a noisy production facility where lots of large scale processes take place. Even though offices are "separated", we still get plenty of background noise when a big run is taking place (frequently). Also, I spend plenty of time on the production floor. Therefore, I take my vacation days, in addition to the paid holidays. I need that time to recharge, and it has nothing to do with me "disliking" my job. It has more to do with my immediate surroundings.
I don't think all early career scientists get to spend most of their time in an office. I've always found being around the hum of equipment to be draining. To the PI/managers who read this-- take it into consideration if all your employees desks are in the lab corners near equipment. I think everyone should have access to break rooms that are at least somewhat sound-proof.
My two cents.