There are a lot of places that let you take long lunches as long as you work your 9 hr/day. I have known quite a few people that go to the gym every day for a couple hrs, some do work their 9 hrs, some don't. Some people are simply required to be there during a core time because they don't work an assembly line, they have to be there for certain things. I had a team leader one time that was never around to be found, he got caught charging time for not actually being at work and he was fired.I think it depends on the type of work done that determines the schedule. For example, I have a GS neighbor that is gone by 6am and is home no earlier than 6pm. M-F with alternate Fridays off. In contrast, I have another GS neighbor (same wage grade) that is gone no earlier than 8am and is home NLT 4pm with same Fridays off.
Also have a contractor neighbor that is a secretary type that leaves at 7:30am and is home by 3pm everyday with Fridays off.
Something just doesn't add up! None of them are part time and they all take lunch breaks!
I have to work around a flight schedule, my normal hrs are 06:30 to 16:00 but many times I have to work through lunch so I can leave at 15:30, some times I have to come in at 05:00, those days I will usually leave at 15:00. Some days I end up staying over several hours.
We are not required to take a lunch as far as I know, but each branch has its own rules.