Calorie Help!

Ok, MFP puts me at 1560 net calories per day. My real question is...Does it hurt to eat as many calories per day as you want as long as you are exercising enough to burn off the excess? For example, I went way overboard today with my eating, I ate close to 1800 calories but I rode the elliptical for 90 minutes. Does this work? I am asking because I have heard you can work out all day but it is diet that makes the most difference. I feel like this implies that you can work out as much as you want but if you eat badly you will not lose weight. What are your thoughts?