It would seem foolish to give up what control they currently have. A lot of people like me would simply use other forms of valued items directly, thereby bypassing any etf system altogether. I can already buy eggs, produce, and fuel with junk silver any time I want.
Getting paid by my current employer in something other than etf would be a serious issue. I suspect I would have to go into business for myself under the radar if I wanted to avoid the conversion issues.
I think doing away with physical cash and going to some form of electronic credits would probably give governments a lot more power/control in general. The Government would do it and could force all businesses to do it too and, eventually, the vast majority of people would be doing it also. At a bear minimum under this type of system, the Government would know where you were at the time of a purchase and what you bought. Personally I think it would be a *lot* worse.