I don’t think trompe l’oeil, like these images of pigeons on a fountain in Barcelona, can be properly described as a disguise, and yet they do play with the viewer’s sense of reality.
One of the things I like about Barcelona is that it wears its politics on its sleeve. There are frequent demonstrations and the Catalan flag is flown everywhere.
So some things are very “up front” in Barcelona.
But in other instances, there are mysteries. For example, the opening and closing hours of everything from banks to stores to tourist offices.
And when to try your marginal Spanish and when to make an attempt at a few words of Catalan.
And then these roll-down devices that cover the windows and doors of most businesses after closing. They are concealing but also revealing — either advertising their purpose or acting as a frame for a bit of graffiti art. I admire Barcelona’s graffiti artists for keeping their work on these surfaces. Almost never do you see graffiti on a wall or monument.
So Barcelona has its disguises but they mainly function to charm the viewers, not confuse them.