Twilight's just received her official government escort license, which allows her to legally take on passengers during a teleport. Unfortunately, the fee was hideously expensive -- enough to completely wipe out all her spare bits. And there's a major purchase coming up which she refuses to put off. So what better way to raise the money than by giving her freshly-approved skill a workout? After all, it's winter, it's cold, ponies will get home all the faster, and since Twilight knows what 'escort' means, so will everypony else.
It's probably best not to bet on that last part.
(Part of the Triptych Continuum)