No, I do not have a suggestion for you accept to say that nearly every exit off of I-4 has the usual run of the mill stores. I would watch the signs for hotels and just get off one of them. There are not that many exits until you start getting close to Orlando. The reason why I suggest checking signs is you would not want to get off an exit that has nothing but another highway.
There's a Publix about a 5 min drive from BCV.
From BCV take right out of resort, left on Buena Vista Dr., right on Victory Way, left on Osceola Pkwy, then right on South International Drive, store is about 1/4 mile on left.
After you pass through Orlando and pass Universal' Start looking for the sign for 528 ( Beeline Expressway) Get off here and go to exit 1 International Dr. At the stop sign go south towards Sea World. As you pass the roller coster get into the left lane,at the stoplight turn left (EAST) onto Central Florida Pkwy. Publix Grocheries will be on your right about a quater of a mile down. From there to get back on to I-4 get back on Cent Fla Pkwy and travel West . Or you can also go South on International Dr to Disney