[esotericn]

It's not this specific decision, but this category of decisions. The EU seems to constantly legislate on "small" things that piss off some subset of the population in a country. Eventually there's a large enough number of annoyances that a majority of individuals are bothered by.

To take an arbitrary example - increasing the age required to obtain an unrestricted motorcycle license.

On the face of it it's not that significant. No-one really cares about this apart from in the abstract. It reduces death rates, and from that perspective it's a good thing.

But there's some small bit of the population that is now pissed off by this, you've told them "wait until you're older", and they don't like that and vote against you.

(It certainly annoyed me at the time despite already having a full licence and already being above the new cut off. No, not enough to vote Leave. I like my citizenship.).

Now multiply that by lots of issues which affect different people.