I just gave a carbon printing workshop in Philadelphia. Upon opening my suitcase at home I discovered a note saying my suitcase was opened and inspected. I am not surprised, considering the odds and ends I had in there for the workshop. They opened up my box of prints -- I hope they enjoyed them! I had a full box of 14x17 X-ray copy film in there -- totally toast, of course, but I am planning on fixing it out and using it as a support material for carbon tissues, so no problem. I carried a box of 11x14 film in my hand baggage, though!

This is because ferry companies treat their passengers as customers. Airports treat passengers as criminals.
Actually on the SF to Philly flight and back again, I felt more like a part of a load of cattle...