Nope, it's not just you. Posties often skip picking up the post from boxes if they're too busy. Particularly those travelling in vans are usually working under pressure, delivering an increasingly large number of parcels as well as letters, and adhering to digital trackers' instructions which are feeding updates to mail recipients. Scooping the freshly posted mail ends up taking second place. (Posties walking with trolleys also usually have lots of parcels, and trackers too.)