Now Google is launching these price extensions on all devices including desktop.
Here is a picture from Google from this Google AdWords Help thread:
Cassie from Google wrote, "to help people compare your products and prices regardless of the device they're using, price extensions can now show on all devices." "Price extensions can now reach more of your potential customers with no additional work. You can continue to use your existing price extension URLs, or take advantage of the final mobile URL field to use a separate URL for mobile devices," she added.
Forum discussion at Google AdWords Help.