I just want to register my protest at the first post in the thread being edited after myself and Barley had replied, thats cheating!
For anyone wondering, the original post was asking about treats in general and did (obviously) say you never know whats in commercial treats. In light of the change to it saying about healthier alternatives like vegetables... Even veg in excess is harmful. Most seeds, heck even most veg, if not fed as treats then they're going to be bad for the ham. Most of a hamsters diet should always be a decent hamster food/diet and treats should be just that, treats. Unless you feed a pellet diet (in which case you trust that pellet diet a heck of a lot) a hamster will always selectively feed to some degree. Their nutritional needs also change throughout their lives. Given that we can never meet anythings needs exactly - not even a humans, I really don't think the odd treat will do them any harm and very, very few treats are truly healthy when you look at them.
I say we give mostly heathier things but I'm fully aware that a few sunflower seeds or mealworms are probably about as bad as the honey drops I mentioned earlier really - and loads of people give mealworms and sunflower seeds far more reguarly than any of my own pets get the honey drops. We moderate even the healthier treats and give a varied enough mix to feel our pets get tasty things fairly often just as part of a balanced diet
I really don't think it matters too much what treats you feed as long as they really are just occasional treats