I absolutely agree. It might seem insane to see someone's calorie count be off by so much, it can be hard to assume she didn't know. But with certain foods, it's just so easy to go overboard and genuinely not realize. I really think for most people it comes from a place of genuine ignorance, rather than conscious lying.

My fiance counts calories but has put on a little weight recently, he's working on it. Anyway one of his problems is he's stubborn about 'eating right out of the bag,' i.e he likes just weighing a bag of something before and after and counting the difference, instead of weighing out a good portion and just eating that. As a result he accidentally ate like 400+ calories worth of sea-salt chocolates with his coffee the other day, because he really thought he 'just had a couple' and stopped at a sensible amount.

Had he not weighed them before and after, he probably would have swore up and down that he only had like 150 calories worth of chocolates (what he originally guesstimated) but it was almost triple that.

Chocolate is an obvious source of dense calories of course, but I still think this is a good example of a well-intentioned snacker going to far without meaning to.