I stopped buying bags of potato chips (my weakness) because I found that if they were in my kitchen, I'd snack on them. Not only because of their salty, crunchy goodness, but because it was so easy to rip open the bag and munch away. Healthier choices take only minutes to prepare, but somehow the ease of reaching into a bag of ready-to-eat food makes it so much more appealing.
If you're trying to cut calories and eat more nutritious foods, then plan ahead and make those foods so accessible, you can't help but choose them. Take 20 minutes to precut a variety of fruit. Slice apples, pears, kiwi, and strawberries, and wash grapes, blueberries, or cherries and place them in reusable containers in the fridge (make sure you dry them off). They're so easy to grab and eat that they won't be at risk for going bad. Not only do I find this little trick helps me eat more fruit each day, but it also helps me remember to eat the produce I buy before it goes bad.