Cutting disability support causes misery and homelessness, which is way more expensive to the state than just giving the person money.
Temporary accommodation slumlords take a huge cut, and the mental health hit of making people homeless prevents them from getting a job for up to a year or two after the change, also costing them extra in therapy etc.
All of this isn't theoretical. It has happened to several people I know.
Cutting welfare always costs more than spending on it. You are a moron if you thing that trying to scrounge pennies from the disadvantaged makes sense.