The ornamental design for a product display and vending cart, as shown and described.
FIG. 1 is a front and right side perspective view of a product display and vending cart showing my new design, the broken lines are for illustrative purposes only and form no part of the claimed design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a rear elevation view thereof; and,
FIG. 4 is a right side elevation view thereof, additionally showing the end rack in lowered position in broken line illustration, the left side view being a mirror image of that shown.