Funny, I've never looked for butane there and as you indicated I would not attempt to travel with it. BIC lighters and cheap knockoffs are readily available.
Just flew with a Vapcap (although it was a domestic, not international flight)
Indeed torch lighters are a huge PITA with TSA - I've heard conflicting reports - don't travel with them, do travel but keep them empty. Etc (I talked to a Cigar store owner who flies down to the Caribbean every year - puts his torches in checked luggage and has no problem).
I tried using a cheapo lighter for my Vapcap, but it takes almost 90 seconds to heatup - so make sure you have a quality lighter, otherwise that heat is going to melt your lighter before you get a few good hits with the vape!
If vaping around the hotel room, I'd suggest maybe using a small candle instead of a bic lighter for the Vapcap (heatup time will be about the same, but it'll be easier and safer).
I think vapcaps are going to be my new go-to disposable vaporizer for trips outside the country - it's affordable and efficient.