Agreed. Fish can easily go a week or two without eating (comes with being cold-blooded), and oscars are no exception. There are too many issues that can come with others feeding your fish that are best avoided. Especially with oscars, I'd be worried about someone overfeeding them because they act so hungry all the time.
If you DO have someone feed them for you, make sure they know how much to feed (or rather NOT to feed) them! Because they'll just keep eating, and eating, and eating...
-sj