The ornamental design for a plasticshoppingbagholder, as shown and described.
FIG. 1 is a front/top/side perspective view of the plastic shopping bag holder with the bag locking bar therof shown in un-latched position;
FIG. 2 is a rear/bottom/other side perspective view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a front elevational view thereof, with the rear elevational view being identical thereto;
FIG. 5 is a right side elevational view thereof, with the left side elevational view being identical thereto;
FIG. 6 is a bottom plan view thereof;
FIG. 7 is a front/top/side perspective view thereof with the bag locking bar shown in latched position;
FIG. 8 is a rear/bottom/other side perspective view thereof with the bag locking bar shown in latched position;
FIG. 9 is a front/top/side perspective view thereof with the bag locking bar shown in un-latched position with plastic bags secured thereto shown in dotted lines for illustrative purposes only and forming no part of the claimed design; and,
FIG. 10 is a front/top/side perspective view thereof with the bag locking bar shown in latched position with plastic bags secured thereto shown in dotted lines for illustrative purposes only and forming no part of the claimed design.