While I agree that it's reasonable to make 18650 based packs not officially user serviceable (because of the spot welding thing and because that would open up liability to repairs gone wrong), at least they should be made so the cells can be replaced by someone who has a spotwelder and some electrical knowledge. Basically give the pack housing a nondestructive way to be opened and resealed.

That way even if the manufacturer decides to switch battery pack standards in a few years, someone with the necessary knowledge can still get some 18650 cells and be fine.