Summer is a great time to take in or even play a game of baseball. But the snack-bar offerings at ball parks have diversified their offerings from the usual sodden hot dogs, nachos and peanuts, not to mention sodas and warm beer. Lucky San Franciscans dine on jerk chicken, crab cakes and wash it all down with champagne. Not many game-goers have access to such posh offerings, but there are ways to eat healthier at the ballpark. If you can bring in a cooler of healthy snacks and bottled water, then you've solved your hunger problem. If not, and you must rely on the concession stand, there are still some choices that won't damage your diet. Fruit is always a good choice, and if you can get that potato baked instead of in French-fry form, then go for it.