Can vacation time be purchased on a pre-tax basis outside of a cafeteria plan?

[EGB]

It appears that extra vacation time can be purchased on a pre-tax basis via a cafeteria plan (subject to rules about use of non-elective vacation days first, no rollover of unused purchased days, etc).

However, can vacation be purchased on a pre-tax basis outside of a cafeteria plan? If it can be, what's the point of doing so inside a cafeteria plan?