I‘m pretty sure they are seed grown. They germinate easily and the seed is plentiful in mast years. They can be grown outdoors as a field crop and don't need any heat or shelter. Nurseries will produce and sell them in great bulk so the price doesn’t seem odd to me. Cuttings are apparently very difficult. But if you have them there’s nothing to lose by trying.

After I posted, I had another think (Painful!!!) about beech.

As a field grown crop, versus even a very easily propagated cutting, the costs are much lower. If the seed is cheap and readily germinates, that would easily explain the cheap price of whips.

I am just curios as I can't think of any decideous bush/tree that can't be propagated by cuttings, of some sort. I know I am going to be shot down for that - there are probably hundreds. ;-))))))))

So. They will go in tomorrow after I put the final layers of soil and compost on. I took them this evening and they are currently living in the fridge.

afaik many of our native trees are grown from seed. Oaks, for example are difficult from cuttings. Why would you bother when seed is so easy? It’s the easiest and cheapest way of producing hundreds of trees and it introduces genetic diversity, unlike cuttings. One of the reasons our elms were so badly hit by disease was that they were mostly clones since they rarely set seed and were all vegetatively propagated from an original introduced by the Romans.