Shoppers at the Freehold Raceway Mall were surprised by a mystery benefactor throwing fistfuls of cash over a walkway railing near the food court on Sunday afternoon while yelling “Happy Mother’s Day.” Sarah Mostafa caught the excitement around 1:20 p.m. while visiting the Monmouth County mall with her sisters, she told NJ Advance Media on Monday. Mostafa was waiting in line at a Starbucks on the mall’s first floor when she heard a commotion from above and saw a man tossing fistfuls of cash to shoppers below. In true New Jersey fashion, the man appears to be pulling the money out of a Wawa reu…