I don't see a problem with the early access games having a price tag while still in development as long as it is very clear that you are paying for an unfinished game. I've only seen that be a problem with that DayZ-ripoff game 'WarZ' and 'Towns' and Valve took the proper steps to remedy both situations. The way I see it there's nothing wrong with supporting a game that you want to see finished.
Admittedly this does lead to a dilemma however. Historically once a game has been made available for purchase it becomes fair game for reviewers. Which seems fair I guess. But virtually any game that isn't finished yet isn't going to score very high (not as high as it would if it were complete anyway), so that may mean reviews hurt sales of games that haven't reached their full potential. Hopefully review sites will use discretion before they slag games that are still in development.
“The greatness of a nation and its moral progress can be judged by the way its animals are treated.” - Mahatma Gandhi