Your notebook with replaceable battery is fatter and heavier than the notebook without the replacable battery, and uses more resources, too (additional shell for the battery, cables, connectors...). Also more expensive to built, as it is more complicated (again, connectors, casing... that need to be assembled). Same for your phone.
I have nothing against people buying such things, if that property is important to them. Just don't force it on everybody.
Actually I was talking about an internal battery that's just sold by the manufacturer, hence the reference to a repair shop. Of course, I don't want to dictate to manufacturers that they have to make everything swappable without tools, but just having access schematics, existing repair guides and spare parts would go a long way.
I have nothing against people buying such things, if that property is important to them. Just don't force it on everybody.