Except I once had a hotel try to do a pre-authorisation on my debit card with no warning (totally random, several weeks after booking and several weeks until we were due to travel). I didn't have enough in the account so they cancelled my booking!
Perhaps there needs to be a public service broadcast: "if you book a room in a hotel with a card, even pay on arrival, they can and probably will pre-auth a significant portion of the projected cost some time prior to arrival, potentially weeks. If this is a problem for you, you need to deal with it."
It's all very well talking about disintermediation and the benefits of people booking direct rather than via travel agencies. But travel agencies were adding some value, which is why corporates still use people like Key Travel or their competitors.
I anticipate that over the coming years money advice type forums are going to be full of people pleased to have saved money by booking flights, car hire or transfers and hotels separately and direct, rather than via nasty tour operators, finding out that when things go wrong, the tour operator provided a rather useful bulwark against the realities of the position.
There are all sorts of received wisdom pieces of advice that fail for some people. For example, the common stuff about "don't take CDW, instead have an annual car rental excess policy it's much cheaper!" Yes, I absolutely agree. But you will often need to provide a €1500 deposit or pre-auth, and you absolutely might have to pay the €1500 excess when you return the dented car, and then claim it from your (stress: your ) insurer. If you haven't got the €1500 to front up for a few weeks, then you need to take the CDW. And similarly for a lot of other situations: the "old way" of doing it often has fewer surprises than the "new way".
As a general rule, if you don't have a credit card with sufficient credit limit to stand all of your open travel plans, you should check how you're going to make it work.