This week, when flying from Stockholm to London, a thunderstorm struck while the plane was being refuelled and loaded. This meant both these had to stop (because of the risk of lightning). While this was happening, I did notice that our luggage was left on the luggage trucks, with a bit of plastic on the top, which did a poor job of protecting our luggage and as a result a lot of the contents of my suitcase got wet and I've had to throw various books/childrens toys away.
Is it usual to leave luggage out like this? Should I be wrapping stuff in waterproof liners like I would when trekking.