The issue is when customs inspects your product. They tear it apart and you are left to deal with an open/possbly poorly resealed package. I import and export lots of stuff.
So what are you going to do when you purchased 50 lbs of coffee and half the bags have been opened. You should note that customs does not reseal your package, they only open and inspect. It is up to your carrier to reseal or not. Depending on the use, it may render your product useless/contaminated.