Matt,
The boxcar is an old B&SR car. IIRC a couple of boxcars were lettered for Ocean Spray products when they were at Edaville. MNG repaired or repainted one of them in a nod to the cars time at Edaville. Ocean Spray is a good sized company that produces (among other things) cranberry products. Since Edaville had the largest cranberry bogs, much of their berry harvest went to Ocean Spray. As you probably know, Mr. Atwood originally built the railroad to serve his bogs and screen house. It was natural to acknowledge the company that was a major customer. Did the box car ever carry cranberrys? Yes, it would have - back in the early years at Edaville. Was the car lettered for Ocean Spray at the time? Probably not as I don't think the car lettering was done until later.
That's the story in a nutshell, the Edaville guys can fill in the blanks.
Stewart