Photoshop is the classic tool when it comes to the creation of banner ads. As you just saw, it even has the tools to automate this process. But unfortunately, not everything could be automated in Photoshop with the use of Action/Droplets. You won't be able to combine different products into a single creative. You won't be able to show a price for every product or use multiple currencies, etc. In short, you would only be able to use Photoshop for very basic automation processes. Use Creative Machine
for everything else.