I've got several bikes, each for a different type of riding. When I'm on my singlespeed, I don't worry about speed, cadence, keeping up with the group, etc. I just ride.

I don't have to consider the gearing, I just ride.

I ride my singlespeed when I'm just out for fun, to enjoy the sun, the birds, the flowers, or even the cows and goats and the sad-looking donkeys that everyone has to keep away the coyotes. My singlespeeds are even set up with a more relaxed geometry to reinforce the "take it easy" feel.