If restaurants are close together, you could be offered a bundle order. Grubhub does this to maximize efficiency with deliveries.
With bundle orders drivers can increase earnings for time spent, for they will be giving the opportunity to receive more order and potentially more tips for less drive time!
Note: Bundled offers are offered as a package opportunity and will either be accepted or rejected in total. Rejecting a bundled offer with multiple orders will result in multiple rejections.