MFP calories. Daily/weekly

Sorry for the vague title! I'm a 25 y/o guy now 208 after being at 240 at 23. I've been down below 190 since, and gone back up.

I've been using MFP to record everything lately and feel confident in my tracking and exercise levels. On days when I include any sort of sports (tennis, softball, jogging) on top of my bike commute I'm under my goal by 400-700 calories, without feeling hungry. Will MFP not work properly if I don't eat those calories? That's a huge meal. I'm in no rush to lose more than 1.5 lb a week. Can those calories go towards having a few good beers at the end of the week? Will that hamper me in different ways?

Lots of questions. Thanks for any help!