I'm curious as to whether they have done a survey or some research into why people don't quit.
If it's because of lack of awareness/education then perhaps targeting areas of deprivation etc and running classes would help.
If it's because someone just doesn't care then chances they won't care about drugs or drink or eating properly etc either. They may take the money eye but could still be pumping their bodies full of equally harmful substances anyway. Voucher surely just frees up the cash to spend on something else.
If it's the "my body I'll do what I like" then as above they will very possibly continue to drink etc we can't take away the rights to someone's body however bad their choices are.
Of its lack of support well the money spent on vouchers could he spent on support surely? Maybe make it mobile if people are struggling to afford the bus fares to the clinics.
What extra support is going to be available as a result of this?
If the current set up isn't working on its not easily accessible enough or people are feeling judged or guilty etc and not wanting to attend or its not working fir them then if there's nothing different in the support set up its going to fail for the Same reasons isn't it? If the person can suddenly make the appointments without a cigarette with exactly the same support as there is now then maybe they weren't that addicted in the first place and just laughing at the idiots handing out vouchers to them.
Unless you tackle the actually reasons behind why they are smoking ajd why they won't or can you quit then it doesn't matter what conditions you put on the vouchers. Selfish uncaring people will still be selfish uncaring people in other ways many of which quite possible still damaging to babies and small children.
People who truly struggle with addictions well people often have more than one kind of addiction by removing on you could alter the balance they have with another leaving them still in an awkward situation.
All this money could sulky be put into more effective ways