They do, just type !g within your query. There are many !bangs that you can use
https://duckduckgo.com/bang
You didn't read the last sentence of my comment ...
Just give me a button I can hit whenever I want Google's result instead, and I'll gladly switch to DDG.
You can easily add a button to do that with something like Greasemonkey. I added a script that adds a button to GitHub that shows the file sizes in an extra column when clicked. Adding a button that adds !g to the front of a DDG query and then sends the search request is easier.
That way, people can use DDG and easily fall back onto Google when the result is slow or inadequate. I know about the bang-syntax (!g) but this requires about 6 touch actions on mobile.