for all we know, the exclusion of alcoholic drinks on the dining plan was a major complaint. I rarely order a beverage besides water unless it's an alcoholic beverage, in which case I also get water. So whenever I considered the dining plan before this change, the option to get a soda, iced tea or what have you didn't appeal to me whatsoever.
I know people will use the dining plan but also order alcohol or extra dishes (or whatever) and pay OOP. Maybe Disney saw enough bills like that and decided to accommodate.
But whatever the decision, it remains an
option. Anyone could still order lemonade instead of a merlot. If there was a point in time to complain about Disney introducing alcohol and its potential impact on WDW as a "family destination," it was when they began offering alcohol
at all, not with its inclusion on the dining plan.