Maybe they can actually make git usable? I've been using it for years; still hate it.

Yes, they basically don't say what they're going to spend the money on.

But it may have been (they hint at this) that they didn't need or want the funding so much as to have AH invested in the company. Taking their investment may create something of a partnership and gives them access to AH's advice/rolodex and encourages future support. It also gives them a concrete valuation to cite down the road.