Quote - ... but I think this would be hard to do with a tiled texture.

Yes, with a tiled texture you won't get specific features like the old plaster (lower right corner) or the bricked up opening (top left) but it is possible to achieve a similar overall effect, that of grungy old brickwork, at a fraction of the memory footprint.

If one was doing a render called 'Naked Vicky with a wall' and the texture of the wall is pretty much the whole point of the render, then I agree that the best way to do it is a full mapped texture made by stitching high-res photos, the memory hit is no big deal. But if you consider that this is just one wall (which is probably going to be partly obscured by furniture) in a room which may be rendered with quite a number of people in it, all with hair, clothes, shoes, props etc, then efficient use of memory becomes more of an issue.

While that particular wall isn't an ideal candidate for a repeated texture,  the floor tiles certainly are. Every white tile is identical to every other white tile. A single square texture having 2 whites and 2 blacks is all that is needed, and you will probably achieve sharper edges in your final render than if you make up a large texture for the whole floor in photoshop.