As a biologist, I assure you not any tissue or plant can be casually tissue cultured. Maybe in theory, but in practice I wouldn't want to be asked to try and turn a bit of woody apple fruit stem or sepal tissue into a viable clone!*

Far easier to just go to the farm during the right season and grab yourself a scion to graft.

*I'm getting enough of a headache from one of my side projects trying to tissue culture some plant tissue that actually has a practical purpose- I'd rather stick to grafting when I can to avoid unnecessarily complicating my life!