There is arguably a significant difference between offering an incentive to make one course of action more desirable and a threat or penalty to make another action less desirable. (This difference need not be one in freedom - I can agree with Steiner that threats don't reduce liberty, but they do render the agent worse off.)
It seems that some are considering a tax on junk food as a way of combating obesity. This, however, seems to me the wrong way to go about things. It ignores Mill's observation that “Every increase of cost is a prohibition, to those whose means do not come up to the augmented price; and to those who do, it is a penalty laid on them for gratifying a particular taste” (On Liberty, ch. 5: p.111 of my edition).
The BBC article draws an analogy with smoking, which it suggests is taxed because it is unhealthy. There is an important difference, however, in that smoking is often harmful to others - hence the ban on smoking in public places, which is not paternalistic and can probably be justified consistently with Mill's harm principle. Arguably a tax can also be regarded as preventing (or at least reducing) harm to others, rather than to the agent him- or herself.
To ban junk food would seem to be paternalistic and thus objectionable. To tax it seems to differ only in degree.
If those in power wish to encourage healthy lifestyles, I think they should employ the carrot rather than the stick - for instance subsidizing fresh fruit and vegetables or doing more to encourage cycling and other forms of exercise.
I think I agree with Bill Rapaport, that the R&R system is not necessarily a bad one, it's just that it doesn't always work as well as it should. I certainly know that I've had plenty of papers improve substantially as a result of a R&R verdict, whether or not subsequently accepted.
On the other hand, journal editors need to exercise discretion. I think that there can be value in sending the revised paper to a totally new referee (ideally along with the original ones), to get a fresh look at it. Problems arise when there's a long time lag involved (though unavoidable at times), when the referees give conflicting recommendations/advice, and when some of their comments are idiosyncratic. A good editor should of course be willing to accept a paper even if the author doesn't do everything the referees suggest.
There is one other problem with the system, which probably affects me more as a referee than an author, and that is that I probably do tend to give to many R&R verdicts. It's a safe 'middle ground' for the many papers that show some promise but also have some flaws. Again, though, the editor's role is important here, since there's a difference between the verdict given by each of two or three referees and the overall verdict given by the journal. The editor needs to make the call when, say, an accept and an R&R verdict ought to be an acceptance (or conditional acceptance), rather than R&R.
That the defects aren't necessary to the system doesn't, however, mean that the system ought not to be abolished. It might be that the chances of having a well functioning R&R process are so slim that we would be better off abolishing it. But I don't think that's so. I think that - while there will occasionally be cases where things go wrong - most journals can manage the system reasonably well (and it is of course open for any given journal to decide how many R&Rs, if any, to give).
One possible improvement would be to have more distinction within R&Rs. Some journals/editors do seem to distinguish minor and major revisions, but it seems to me that R&R can sometimes basically be a conditional acceptance and other times is no more than a vague willingness to look at the paper again if you completely re-write it (rather than permanently rejecting it). Perhaps it would be useful if these were always clearly distinguished.