Presumably he means taking his vacation days so he doesn't have to put in any days of work in the 2 weeks after he puts in his notice. I'd guess he isn't American -- the term "holiday" is interchangeable with "vacation" in most of Europe, for instance.
That being said, your point about bank holidays is a good one. Never give your company free labor -- they'll never give you free capital.
That being said, your point about bank holidays is a good one. Never give your company free labor -- they'll never give you free capital.