I'd argue it doesn't just achieve nothing, it works against the cause in two ways:

* First, as others have said, it builds resentment in those that see it as not worthwhile compared to other things and who are negatively impacted like how you describe.

* Second, which I haven't really seen people bring up, by succeeding at a visible but inconsequential change, the activists who brought this about are less likely to bother with something that actually matters.