I remember once having the same when I was sent a replacement charger for an iPad from Apple. Duck Head, Adapter and Cable all in 3 separate very large boxes from the same facility. Labels printed at the same time an all.
I imagine there’s too much pressure on the dispatchers to just slap a label on and get it out, rather than try to save on packaging and shipping costs. With the business courier rates the difference won’t be too noticeable to them than if they packaged it all in one box, compared to if you or I paid public rates for the same number of parcels.