Before I answer, we wish that we were whole foods people, we strive towards that, but we don't always make it.
Add to that, my dh's labwork in December showed pre-diabetes, so he's making a concentrated effort to avoid simple sugars and carbs. That said, for snacks, I buy: (all of these aren't all the time
cheese and whole wheat crackers
cheese and apples
veggies (celery and carrots almost every week, then radishes, turnips, snow peas, cucumbers, cherry tomatoes, whatever looks good to eat as veggie sticks with or without a dip)
a sour cream based dip for veggies (i just usually wing it from the pantry)
hummus (I make it; it's easy) and either veggie dippers or pita
pimento cheese (make this, too) and celery and/or saltines
refried bean dip--beans, salsa, some cheese, heated
a black bean and corn salad I make--we eat it as a side dish first, then the leftovers as a salsa/dip
peanut butter for crackers or celery or carrots
my childhood treat--saltines with horseradish and a tiny bit of ketchup (kind of like deconstructed cocktail sauce)
jello (see--really not 100% whole foods LOL)
yogurt (we buy big things of plain, then add fruit or jam or honey)
cinnamon toast (toast with sugar and cinnamon--really easy)
Before the diabetes scare, we also had a half gallon of ice cream in the freezer.