You will be happy to know the send it on "airplane as luggage with passengers" business models are now seen as failures by most Silicon Valley investors as well as some YC partners. It's been 5 years and there were many of these companies - the investors got burned
How do I know? I run a YC funded company that legally imports :)
Here are two different YC startups that relied on tourists smuggling goods to avoid import duties:
https://techcrunch.com/2014/08/13/backpack-connects-you-with...
https://news.ycombinator.com/item?id=10998377