Why landlords have no excuse not to insulate

It's shocking some of the a stories people tell of landlords refusing to put in even basic insulation in lofts, let alone cavity walls.
There's no reason why they shouldn't as there are grants and schemes available. The Landlord’s Energy Saving Allowance page at Direct Gov is worth a look - if you're renting and think your house needs more insulation then send the link to your landlord.
LESA is a tax allowance (not a cash payment) that allows you to claim up to £1,500 against tax every year.
Part of me wonders what other businesses are subsidies like this though.