1. ♪ Last night a food storage container saved my life ♫ These little buggers are great for pre-measuring 'just enough' of whatever you are taking with you.  I pack spices, sauces, condiments, pasta and rice into one of these bad boys.  When the ingredients are gone, they also double as a great place to keep leftovers and fit easily and air-tightly in the cooler.
2. Powdered drink mix Each snappy camper needs only one water bottle.  The magic of  Crystal Light does the rest. It's like Stone Soup for drinks.  You can pack a weekend worth of beverages in your pockets.  Now try that with a case of Diet Coke (and then send my a pic, please when you do!)
3. Know what you can leave behind Use the power of the information superhighway to scout out the local grocery and (if applicable) liquor store before you go.  You may be able to save an entire cooler's worth of space by planning to pick up eggs, milk and a thirty pack on arrival.  Note: not worth it if you need to drive a town or two away when you get there.  It's snappy camping, after all; not a scavenger hunt.
4. You need less than you think you do My dearest, dear heart camping and life companion just can not understand that one DOES NOT NEED 4 sweatshirts for a 3 day trip.  Hopefully, dear reader, you are a quicker study.  You don't.  Nor do you need enough wardrobe changes to make your own off Broadway play.  It's camping.  Pretty much as soon as you put your fabric freshener fresh sweatshirt it will smell like smoke and be covered in dirt.  Trust me, I know.  We have conducted independent double blind empirical studies and get the same results every time.
5. Thermal Blankets Give you all the warmth at a fraction of the space.  One or two of these will get you through a chilly New England spring or summer night and give you enough room to pack the important things, like tiki umbrellas and portable blenders.

 With a little advance planning, you can bring all of your snappiness with you without renting a minivan or Mack truck.