No problem! I went back and reread and there it is, second post. It used to be that there had to be intent present to commit a crime. The government realized they could prosecute many, many more people by stripping out the intent requirement and did so. Try depositing 10,000k cash into your bank account without documentation. Just because you didn't "willfully break the law" won't stop you from becoming a felon.
There is no defense in a case against the government. This isn't a logic or philosophy college course. The gov't could care less what your excuse...logic... reason is. If a snake belonging to you goes across state lines, they can prosecute you. Doesn't matter if you try to pin it on Fed Ex.
I suspect Fed Ex won't even know for 100% until a case goes to court. I also seriously doubt that Fed Ex allows people to illegally ship wine as you suggest to make an extra couple bucks off shipping. It's an absurd notion they turn a blind eye to it.