Originally Posted by LilyWDW
My guess is that they don't want to deal with it. There have been reports (from guests and CMs) about how people get the dining plan with no real understanding of how it works. So, they just make it easier on themselves and just say that the "make your own" section is not covered by the dining plan instead of having to deal with how many of what sort of toppings might be covered.
It is really about Via Napoli not being owned by Disney. Thus, they go by their own rules to maximize their reimbursement from Disney for dining. They basically offer the minimum required, to still be allowed to participate in the dining plan. Thus, they don't offer any of their specialty beverages, nothing considered an "add on."
Just as most Disney dining plan guests seek to maximize value of the plan.... Via Napoli wants to squeeze profit out of their reimbursement.