These prices are the all time lowest prices for these games (according to price tracking/price comparison site).
However, GOG still seems to give The Witcher 1 away for free of you sign up for Gwent Card Keg: https://www.gog.com/gwent-welcome-bonus
Even so, if you want to support and reward the devs buy it for $1.49 AUD.
While some people might say The Witcher 1 is a bit too outdated to play, if you do not mind older graphics I would definitely say it is worth it - I enjoyed it when I played it last year on GOG.
The Witcher 1 Enhanced Edition: https://www.humblebundle.com/store/the-witcher-enhanced-edit...
Mod update: Removed duplicate from title.