Really it's fairly simple. Most people don't like change to any of their rituals.
Very few people know how to adapt anymore. To anything.
Agreed. Most people are creatures of habit.
However, as WGT App changes overtime and more game types like skins, match play, stroke, Cabo & Whistler added and features enhanced that can complete with the web version some people may decide to give it a shot and stick to it.
Do not forget, many of us spend quite a bit of time on the game daily either playing multiplayer or many single players (many both).
So lets hope that individuals who are saying they will not make the switch will make the switch for any aspect of the game they may like and miss. If it's the social aspect, that is a part of it. but the current head to head it's limited to a friendly 3 or 9 hole random game via invite a friend or random 1, 3 or 9 hole games in coin games. On the current flash there are many other types and whomever creates it can also select the course, and style of play which is much more fun than the mobile / PC app are currently on.
Time will tell and hope most people don't leave and can adapt.