First, I want to assure you that you shouldn't feel pressured to eat "wheat free, dairy free, or vegan." People only need to avoid wheat if they are allergic, sensitive, or have Celiac disease (my youngest has CD), and people only need to avoid dairy if they are allergic, sensitive, or have lactose intolerance (my youngest, again.) Eating vegan...the absence of ANY animal products...well, that's really a lifestyle choice, and in my opinion, not a very healthy one. So please don't feel guilty...you have common sense, and you aren't jumping on the bandwagon. Good for you!
Good nutrition is important, but it's more about balance than extremes, and you definitely don't have to follow fads or feed your child a wholly organic diet to feel good about yourself. I'll give you examples of my children's diets, and some suggestions for replacements that are easy to do. I'll refer to them as 7 and 2, because those are their ages and their diets are completely different.
7, for breakfast, alternates between the following: cereal, oatmeal, pancake, waffle, french toast, sausage and eggs. Included is fruit and watered down (50/50) 100% juice.
2, for breakfast, almost always has a GF waffle topped with peanut butter, fruit, and water. She will occasionally eat cereal.
7, for lunch, likes chicken, sandwiches, pot pies, bagels and cream cheese. I always serve a few sides...veggies, fruit, cheese, crackers, etc...and she drinks skim milk. Instead of buying chicken nuggets you can make your own, which really doesn't take that long, and bake them in the oven. Sandwiches can be made on whole wheat bread and include lean meats like turkey, chicken, etc...and nothing wrong with a little roast beef.
2, for lunch, will have yogurt, tuna, GF Annie's mac and cheese, a peanut butter sandwich on GF bread, GF whole pollock fish sticks, tamales, etc...also has fruit and veggies with these. The mac and cheese is no more than once a week, and it's not that bad, honestly...better than Kraft. I try to limit the tuna because of the mercury, but she does really like it. I have quit buying chips, because they are one of those things that no one can seem to eat in moderation.
For dinner, we always have a well balanced meal...meat, veggies, grain, etc. Everything from tacos to meatloaf, pork loins to roast, grilled cheese and tomato soup to spaghetti, homemade enchiladas to shrimp salsa, stir fry to homemade pizza, etc...you get the idea. Regular, home cooked meals...and when America ate this way, instead of at restaurants and McDonald's on a regular basis, we didn't have the problem with obesity.
Snacks are yogurt, fruits, cheese sticks, cereal, rice cakes, air popped popcorn, etc.
But ALL that being said, NO one is perfect and you don't have to be! Did I buy my kids a box of Mike and Ike's today at the grocery store? YUP! Do we have frozen yogurt in the freezer? YUP!! Did I buy a bag of mini marshmallows because my toddler asked? YUP!! Did I buy two candy bars and hide them above the sink for myself later? SURE DID! (Oh, I went grocery shopping today.) :) There is nothing wrong with this stuff...in moderation. Do I keep it on hand...as in, if I run out, do I make it a point to buy more? No. I buy a set amount of "treats" once a month, and when they are gone, they are gone.
Please don't feel guilty. If you slowly make small changes, within a few months you will see a big difference. You're doing fine!
**I do want to add that you can absolutely take strides not to have an entire day full of fast food, processed garbage, SUGAR added to milk, and juice. I realize we all have our off days...I mean, I'll grab the cereal too if we have somewhere to go and I'm in a hurry...but people can make a huge difference by using common sense...i.e. not adding sweetener to milk, or cramming snack after snack in between meals. I get the impression that this isn't your issue!!! :) I honestly get the impression that you understand and implement a well balanced diet for your children.
And I DO want to go scarf down a bag of tortilla chips. I do that, occasionally. ;)