I still don't get it, the first half of your post backs up your original stance, whilst the second half agrees with what I said that it's not a necessity (for basic things you can use your finger).

Doesn't the irony you highlight in your post regarding people buying "those little rubber iPhone/iPad styli like hotcakes these days", indicate that people find it easier to use a stylus for certain things? A stylus is certainly a part of the UX, but not an integral part.

Using your finger is not the best option for all scenarios, if that was the case we would have been dipping our finger in the ink pot instead of a quill.