This might only be relevant to Southern California residents, but it might apply to visitors from other areas with Kroger-owned grocery chains as well.
I recently became an AP again and when I did so, I purchased the $99 two-day, one-park-per-day tickets at a Ralphs Grocery store using my Ralphs Rewards club card. The four $99 tickets then served as the $80 down payment toward the payment plan, but they also sell gift cards for each of the various AP levels. The reason I'm mentioning it is because they have a promotion where you earn double points on all gift card purchases. So four $99 tickets (from the gift card kiosk) translated into 792 Ralphs Rewards points, or nearly $8 in free groceries in the next calendar quarter. A couple days later I also purchased a Disney Gift Card from Ralphs where you can put any amount on it you want. Another $200 there translated into $4 more of Ralphs Rewards.
It's not a huge savings, but if you're already a Ralphs Rewards member, it makes sense to buy gift cards there and then use them instead of cash inside the parks. I've found that even the small snack carts (churros, cinnamon rolls, etc.) seem to accept Disney gift cards for payment.