Just park further
Not convinced? How much of the food does it come out the other end? Certainly not the same amount as that went in! much much less. Now.. the food don't just disappear, they appear elsewhere. My tale of indigestion in Bak Kut Teh has said enough about this.
If you need inspiration to start exercising, maybe this post might help you. Still too difficult? Take the public transport! It'll force you to walk a longer distance to get to where you want. Plus, you're helping the environment by having less cars on the road. You don't even have to contend with the traffic. No more cursing in the car.
If you really need to take your car, just park further. At a grocery store today (a place more affordable than Orchard Road in Singapore!), there were plenty of cars contending with the parking space nearest to the store! Those cars were causing a lot of fumes both inside the car and outside the car, not to mention the congested traffic. Just one row down, there are much more car parking spaces, less cars to contend with, no traffic jam. And it's only one row down! So please, just park further, it'll help walk off the extra food if you did go for a buffet lunch/dinner.