In my country you, as a civilian, fly the national flag for the equivalent of July 4th, and for big personal events like graduations. Flag merchandise is of course also worn in support of the national sports teams.

Outside of that the main people flying national flags are government institutions, who usually have it up right next to a European flag and a flag of the institution, like a local municipality.

The European flag is also plastered over billboards next to all kinds of EU-funded construction projects, of course, and is on literally every single Euro bill.

So no, someone's feelings about an institution are not inherently linked to the success of its empty propaganda campaigns.