"Earned" calories through exercise

Yes MFP has built in your deficit. That being said most people only eat about 1/2 of the earned calories back.

I guess maybe I do things different here, but it seems to have been working for me.

When using the MFP suggestions I put that I am sedentary for my activity level even if I were to work out heavy during the week, that way MFP only calculates my calories for me based on if I was doing no workouts. There are two main reasons for this for me.

1) Like a lot of people I am not always faithful when it comes to making it to the gym and working out. If you over estimate your activity level then MFP ramps up the calories you should be taking in during the day. Then if you under perform, you are going to take in a ton more calories than you spend, causing you to gain weight. By choosing the lighter activity levels I make sure that I am always safe if I perhaps don't have a good week of working out but still follow my caloric intakes which are low when you choose sedentary.

2) It provides me the opportunity to have a good post workout shake to "eat back" the calories I just burned off when I do work out. This allows me to enjoy something delicious yet healthy while at the same time not worrying about taking in too many calories over all for the day.

Like I said, I do it different but it has been working really well for me and my fiance, (Though I will say I have an office job with no manual labor so choosing sedentary works for me, if you have a more physical job then lightly active would be a better option) I have been still losing an average of 2-3 lbs a week without feeling starved or having to beat myself up if I did not make it to the gym consistently over the week.

Either way you do it, the best thing to do is just get in the habit of inputting those calories every day. I use the MFP app on my iPhone and after a few weeks it becomes second nature.