Blast's experience:

72 hours is only enough if you don't mind waiting for hours in line with angry, stinky people(pic coming) to get a bag of ice, a jug of water and and MRE "Happy Meal" (pic coming). That is after you've burned half you gasoline trying to get to a distribution center. Then you have to do it again the next day, repeat every day until things return to normal.

If you only have 72 hours worth of food/water/batteries you are going to be miserable. Stock up as much as you can and turn the apocolypse into a vacation. We keep our pantry stocked to the point of bursting so my experiences with the 4-hour lines of stinky, angry people has just been taking pictures of them and feeling a combination of pity and smugness).

This applies to bugging-in.

-Blast