Pregnancy grants

There's been a lot of comment about the UK government's (re-)announcement of a plan to give a cash grant to all pregnant women, with the stated aim of:

encourag[ing] them to eat better and improv[ing] the health prospects of their unborn child.

Chris Dillow points out that this won't be the effect:

... if couples get an extra £1 of child benefit, 49p is spent on drink, and 40p on adults' clothing. If single parents get an extra £1 of child benefit, 71p goes on women's clothing.
If child benefit doesn't get spent on children, it's unlikely that support for foetuses will be spent on foetuses.
[...]
What Alan Johnson is doing here is the politics of symbolism. He wants to signal that he cares about the ickle-wickle kiddie-widdies. Results don't matter

But this is more than just symbolism. It's vote buying, and results do matter.