Yes absolutely noticed this and it's something I've been trying to document properly for about three years now. In my own property in Warwickshire the orbs in my photography are almost exclusively confined to the hallway and the back bedroom, never the kitchen, never the lounge. I've ruled out dust by controlling for air movement, humidity and light source angle.
My working theory is that certain rooms hold residual electromagnetic charge differently - older properties with irregular wiring, damp stone walls, that sort of thing. The geometry of a room might matter too. Narrow corridors concentrate whatever energy is present.
What I'd really like to know from others is whether the orb-consistent rooms in your locations correspond to areas of reported activity by other means, EVP, temperature anomalies etc. In my case they do correlate strongly. Would love to compare notes with anyone who's been systematic about this rather than just snapping random photos and hoping for the best.