What are customs duties and what would be infrastructural costs to distribute the pants?

BTW – if you just want to pay for part of airfare to Europe, nothing wrong with bringing a high-end iPhone or two (one personal, one “work”) with you to the right country and “losing” them on the trip. iPhone prices in Poland and Czech Republic are about 30-35% higher than unlocked price in the US. Same might go for MacBooks, haven’t checked recently.

You can easily make $200 per device and spend the money on your trip, thus negating currency exchange commissions.