Exposure is worth exactly nothing. See how many internet artists and content creators will do stuff for free because of "exposure" - hint, it's zero. It's worth as much as "raising awareness" in the lexicon. It's wordsalad that accomplishes nothing, but makes people think they're doing something worthwhile.
Have you ever, ONCE, been approached by a community member, parent, etc, and had them ask you to perform at an event solely because of how well you performed at graduation? Have your kids gotten wedding performance gigs out of it? What, then is all this "exposure" getting you?
If you want to get people interested in your program, do things they'll care about when they care about them. What you're talking about can be accomplished with a cable and a Youtube playlist, even if it's your own band. There is no reason whatsoever for your kids to go do this in person, with all the headaches that Graduation entails.