You may need more calories than someone at a sedentary job, but having a job like this in general will not add to your fitness past a certain point. You already get a daily living modifier, and counting daily activities is effectively double-counting, so yes, you likely are overcounting.
However, this may help you determine if you do indeed need to increase your *base* calorie range to account for extra activity: www.sparkpeople.com/community/ask_the_expe
I'm not sure how this technique will apply to your particular job, though. It's not adding to your fitness, and your body had no doubt adapted at this point... it doesn't burn as much as doing that actual activity would for someone who isn't doing it daily.