Yeah, transitions for park-wide things can be kind of messy, especially if they're not clear on phasing things out. Plus, you'll always have a few bleeding hearts who will break the rules for guests that aren't aware of the changes.
I agree with the 1-2 drink people dropping out. I know that I don't renew my chip every day because I don't need 8 sodas in a day, but I still think the money pile stacks up higher with the $8 refills than it did with the $0.99 ones, especially if people aren't actually refilling 8 times and are just looking at the $8 as being able to buy a $3.29 soda three times and save money, e.g. people who never knew about the red cups in the first place.