I thought working 40 hours was the standard, but 9-5 with a paid lunch is less than 40 hours. So, the math never made sense.
The only place I heard of people working 9 to 5 was in Dolly Parton’s song. I’m enjoying reading everyone’s answers though, and I’m hoping someone chimes in that has actually worked a traditional, in office 9-5.
Unfortunately a lot of employers expect eight effective working hours a day so you'll see a lot of people working 9-5:30 and stuffing a Sammy down their gullet in their ten minutes of freedom in the middle of the day.
We're guaranteed the ability to take a lunch break without retribution but it being paid or unpaid is less of a guarantee - especially if you're salaried (aka hourly but not paid overtime).