Edit: Hobbies certainly aren't practical, but there is often a practical aspect associated with them used as a justification, e.g. for having fresher vegetables or unusual varieties not sold in a supermarket/co-op. I bring up cost with woodworking as it's a notoriously expensive hobby, especially second-order costs such as the decision to own a single-family home or a larger vehicle.
Next is this :
> DIY furniture is not cheap compared with mass-produced even without considering time,
Do you honestly believe that "mass-produced" furniture is anywhere near the same quality as DIY?
Ikea - Where you can buy a bookshelf which will not be able to hold the weight of books.
DiY - Where you use dado's and plywood and end up with bookshelf's which can easily hold a few hundred pounds.
There are things worth far more than money.