Don't pay for postage online, and if you do, use a fake name, & a Greendot card/Re-Usable debit card. then you should have no problems.... I never thought about them tracing the stamp barcode back to the sender. I doubt they'd do that if it was less then 1 lb.
I sent weed from ohio to florida packed in coffee grounds with a fake name and return address...not one problem.