A moral issue, a criminal issue and a personal issue. I believe counselling and a managed rapid detox should be offered initially. Maintenance, however, is both wrong and ineffective, and should not be paid for by the taxpayer.
Inpatient detox costs far more than methadone maintenance. I can see where you are coming from, but withdrawing methadone maintenance would be a bad move for society, and would lead us back to the pre-methadone days of the early 80's where acquisitive crime increased exponentially throughout many a community as a direct consequence of the emergence of heroin being sold within working class communities. I don't think anybody wants to return to those days.
There are two things that annoy me about the substance misuse treatment industry, and it has become an industry, just like most other health and social care services. One of them is that any EU junkie now has the right to plonk themselves in the UK and start demanding free methadone. I've absolutely no problem with people migrating to the UK in order to better themselves and contribute to society. But no way am I OK with people who come over here and demand free methadone whilst pimping or selling themselves on the streets. Immigration to the UK should be based on factors other than your nationality, as allowing some people in just because of their nationality, whilst excluding other people based on their nationality (non-EU), is quite clearly racist.
The other thing which annoys me is when people think they have a right to go to rehab. They don't. And I feel a mixture of laughter and frustration when people threaten legal action over not going to rehab, or even just a delay in going to rehab. Go ahead, commence legal action, see how far you get! People don't realise that they are lucky to be dealing with a service that still has a process in which people can be sent to rehab, as many areas have stopped it completely, even if they don't admit to it, and people will only get it in extremely exceptional circumstances.
The cost of rehab is a joke, and the success rates make them very bad value for money. I don't think it is right to be spending between 6k - 12k on people who have chosen to spend their lives getting wrecked all day long, not with all the cuts that are taking place for people who have serious health or social problems through no fault of their own. I think it's quite similar to these people who somehow get the NHS to waste 6k on a boob job for them. NHS and/or local authority money should not be wasted in this way.