In answer to some of the postie suppositions.... the bikes were taken away because someone did a costing and found vans were cheaper.
When we had bikes it involved a dedicated duty to maintain and service them, so that job has gone, and wages saved. They also had to be replaced every 5 years (that was health and safety) and the Pashley bikes were not cheap. And as most posties have between 6 and 8 bags to deliver, these had to be loaded on a van (sometimes 3 or 4 vans, depending on the size of the delivery area) and dedicated drivers delivered these to various shops, post offices and kerbside lockable boxes for the postie to collect as he finished each bag. These shops etc were paid by the bag so another expense spared.
Now the postmen have vans and can take their own bags, so bag delivery drivers wages were saved, a shop remuneration recovered.
As I said, someone did the sums and decided vans were cheaper.
The reason you can't put 3 posties in one van is that there are usually only 2 seats and there wouldn't be room for all 3 postie's bags, and they may all be parking on the estate because that is the easiest place to park, but dispersing throughout your village.
I have worked in a few service industries, including Royal Mail, and had to bite my tongue on many occasions when harangued by members of the public about the reasons why this or that has happened. And there's always a logical explanation, but not the one they had thought of.
When I first became a postie, I was offered a lift home by a colleague's brother. As we sped down the road, he very closely overtook a postman riding home on his own bike, making him wobble and offering a one-finger salute. The driver just laughed and said "I'll go closer next time, there's plenty more where he came from!"
And in answer to the original OP the one thing I haven't seen for a long time is a mobile knife grinder.......Oh! and Spangles