I find these two comments an interesting contradiction. You claim to be a huge treat giver. Yet you don't think you will go so far as to offer treats at mealtime? Mealtime is the time for food/eating... that's a more logical time to dispense food! :)
I think a treat helps them understand that they did something good besides saying 'good horse' and giving them a pat. If you use them for like teaching them tricks or something like that. And I think that there are some are us that just like to spoil our horses. Some like to give them a warm bran mash, others prefer just spending extra time on them, and others like to give treats.
What I mean that I wouldn't give them treats at meal time is that I wouldn't feed them treats all day and then pop a few more in their food bucket. I usually only give treats like I said above, for tricks or stretching excerises, and occassionally while I'm grooming. I feel they have to 'earn' the treat somehow. Not just getting one as part as their meal.
If that's your thing, then fine (as long as you realize the potential of creating a mouthy/biting horse by hand-feeding).