She had an intention of cancelling that was exactly 50%. In other words, she fully intended to use the booking, until she found out that it wasn't fit for her purposes, at which point she exercised the cancellation option that they charge more for.

If I pay extra for a refundable hotel booking option knowing that there is an equal chance of me using it or cancelling it, I don't think it is fake, it is simply uncertain. When I exercise an option for service that has been sold to me, I certainly don't consider that to be a nuisance. She was playing by their terms and conditions.

Given that they don't define what a "fake" or "nuisance" booking is in their terms and conditions, it is perfectly fine to argue that a booking made with an uncertain, but genuine, intent to use the service is neither "fake" or a "nusaince", especially given that cancellability is prominently advertised as a feature of the booking. What possible other purpose would offering cancellability serve if not handling uncertainty in travel plans.