The practice of homeopathy does harm, and has killed.
It's not the sugar or water that does people in, it is the belief they are encouraged and convinced to have in sugar pills as effective.
And a belief that "alt" therapy is safe/good whereas medicine is "evil big pharma poison chemiclas" and to be avioded. A line homeopaths are not adverse to pushing.
whatstheharm.net/homeopathy.html
That is before you investigate the extent to which western homeopaths have got involved in pushing the anti big pharma v lovely homeoquack line to increase sales of their sugar pills in Africa. HIV Antivirals and maleria are two areas that homepaths have leapt on with great human cost.
As for the idea that homeopath believe their "meds" are harmless....
Homepaths believe that the weakest dilutions are the most powerful, and do believe that you can overdose on them. They have to really, you can't claim more dilution means greater strength and not follow through to the logical conclusion that at some point super potetency is reached.
The first deliberate "overdose" on camera I saw was about ten years ago, when a homeopath sent a skeptic a vial of 200c (one of the higest dilutions) remedy for insomnia and baldly stated that if the guy took them all he would die.
Well he did, but had no adverse effects. I think that first challenge from homeoquack to skeptic was what started off the "mass homeopathic overdoses" outside Boots.