The funny part is that your expectation is probably "I get the legitimate 1 hour of work instead of them taking a nap" but the reality is "I get 4-5 hours of poor quality work after lunch due to lack of nap".
This, however, is basically "Should my employer give me a benefit because I'm tired from working for other people?", which is, well, let me settle for "definitely not the same question".
In this case you can make a strong case that the employer in question isn't so much on the hook for providing nap time, but justified in firing you for not being able to keep up your end of the bargain because of your choices.