Yep, that's the ticket. You can keep track of who has been fed either with a pencil and paper, or what I do which is give them a snack right before I grant their favor for the day (not when I take their order). Or go down the line of houses in the evening when most of them are home. If a peep misses one day's meal it won't harm them. If they miss 7-15 days, they'll be in danger.