Now more than ever is a brilliant time to let businesses sell digital gift cards to their establishments.  
Here is a screencast showing you how to do this: https://www.screencast.com/t/x3mrHFsQaw

You don't even need to mark down the gift cards. Sell them as $50 for $50 to help the restaurants. Add a new category on your site called Gift Cards (Site Settings >> Categories) and offer gift cards as a category to help out businesses as they struggle through these next few weeks.
This Gift Card Category type looks a little different than your standard offer pages. Example:
giftcard-category.png

In step 1 of proposal / contract creation process, Choose Gift Card Voucher from the dropdown menu for Proposal/Contract Type.
There is a separate Gift Card voucher template than there is for the Regular vouchers (Design Center >> Page Templates) and gift cards can be redeemed in increments.
Example Gift Card Voucher Template

gift-card-vouher.png