Different strokes for different folks, I'd say.
I go touring to spend time outside in the countryside so I aim to maximise the cycling time available on my trip. Sometimes I'm only able to get a week away from work - spending a day or more travelling to my destination, and the same back, seriously cuts into riding time. A long trip on local trains can be risky too as any delays/cancellations are unlikely to be honoured by other train operators. (If your TGV is cancelled then you have rights to allow you to take the next train, free of charge).
I don't particularly enjoy flying, even more so with a bicycle travelling alongside me. But with an early flight I could arrive at my destination and ride 75kms before dinnertime.
Love the idea of better bike hire provision but it's unrealistic. It's hard enough finding somewhere to hire bikes, even on more popular routes (
viewtopic.php?f=16&t=135106 as a recent example). And any bikes that are available tend to be unsuitable for loaded touring.
A brompton fits neatly into the gap here, IMO. Maybe not for a camping trip, but should be suitable for credit card touring....