Businesses need to recoup their costs to be profitable. If this amount represents the cost of employee PPE/ sanitation it should become part of overhead and rolled into pricing as a percentage increase. Listing as a line item surcharge is a poor business practice (lazy) and leads to customer dissatisfaction.
I agree, a more tactful way would have been to increase the pricing across the menu items or to simply announce on the menus that a set surcharge will be added.....people hate surprises!