We've never had a problem with cars, planes or staying in hotels or with people. If on long car trips, I treat it like a night nappy but with a PUL cover. Take extras on planes, you never know what is going to happen. And when staying with helpful relatives wash them yourself
They always seem to feel the need to put extra detergent in or tumble dry them so they're nice and soft.
We've found it useful to buy a packet of flats when we get there and then just leave them there, and use them as night nappies or around the house. It just means packing less.
Deb