Here, we can see an example of that in action
http://www.vox.com/conversations/2017/4/24/15286624/race-rural-america-trump-politics-media
To review:
Less is used for non-count nouns ("Humans have less to gain by looking for bigfoot, and more to gain from actual science"). Fewer is used for count nouns ("There have been fewer reports of Bigfoot since the advent of the cell phone camera").
In one case, you can count something ("15 items or fewer"), and in the other case you're using a much more figurative comparison.
Irksome, indeed.