Sometimes I find it hard to buy proper crisps these days, so often there are baked crisps. To me these just taste too sweet as all they have done is replaced the fat with sugar and fat is probably healthier in the first place.
Read a thread where people were saying pizza once a month was fine. In my house we have pizza night, chips night and burgers night once a week. This means that out of 21 meals 18 are healthy. I think its important to feed real food otherwise once they grow up and move out they will probably binge on junk if they were not given any growing up. Ive seen this happen to a few people raised on a strict diet.