Am i being taken for a ride by my roomates friend?

My roomate and her friend Roxy came home late last night from shopping..Roxy (my roomates best friend) asked me if i would do her a favor..she wants me to go to Walmart with her tonight after i get off work to return a blanket and a bottle of perfume that she doesn't want..now she said the reason why she can't return it herself is because she once again lost the receipt and that walmart will only let u bring back items without a receipt 3 times in one year..Now why doesn't she just simply ask my roomate who is her friend?...i thought about that also..I'm thinking that she also has done it 3 times in one yr...Do u guys understand what i am saying?....what should i do?