I've heard that a lot of medical conferences take advantage of the fact that doctors need to fulfill a quota of "professional development" every year, so they set themselves at very pleasant resort hotels.
When I was in grad school in SF, my Aunt who was a doctor (dermatologist) attended the annual dermatology conference there. She invited us out to dinner at several of the nicest restaurants in the city and we were treated to the full course experience, plus lots of nice wine.
At the end, all the doctors fought to pay the bill because it was a tax write-off (business expense? I don't know how professional doctors with practices account for these things). As a grad student in SF living on $25K/year it was quite an eye-opener.
Or to be more specific, you can take your whole family to a tropical location and pay for it out of pre-tax money, effectively getting a discount of whatever your tax rate is.
At least that is how it would work in the UK if it was allowed.