Actually, no they didn’t. The Greek press covered their holidays extensively, but it was curiously blacked out in the British press—which says everything about how the UK media actively protects them from scrutiny.
Furthermore, there is absolutely zero proof it was a standard commercial rental. If it had been rented legitimately with their own money, the palace PR machinery would have briefed the press immediately to shut down the controversy. The total media silence and lack of an official paper trail strongly indicate it was an un-vouched, borrowed favor, which is exactly why the British tabloids refuse to report on it.
But that's not the issue. The point that they still go in mega expensive holidays 5 times per year at least. Just that the press is not allowed to post pictures of it