Support informed me that they don't auto-backfill Meal Plans when a charge for a mealplan is applied just in case the charge needs to be applied without editing the campus life record. I can't imagine what that's necessary but I don't work in Student Billing. So maybe it is.
But it causes a headache here when someone forgets the correct proceedure. So my proposed solution is simple: ask.
When someone adds a meal plan charge outside of the correct meal plan proceedure just ask "Would you also like to add the meal plan to their campus life profile?" Yes or No?
So when you add a charge, you can decide if it should sync or not. Not automatic one way or the other. Just ask.