In all fairness, how exactly do you expect DDG to know what you want from this, without doing some sketchy privacy invasive scanning of your search? If you really want a company to scan your every search and then tailor the results specifically, then by all means use Google, that's what they're good at!
The obvious heuristic is “does this search term frequently appear on local result sites?” For example, “brick suppliers” is a search term associated with websites that have a business address, whereas “python string length” mostly isn’t. The search engine already has to scan your search to know what to send you from the index; it doesn’t require anything more than that to be able to guess at the intent of specific searches.
If true, then DDG could apply the same heuristics about location-sensitivity for everyone's searches and improve the results for everyone, without any tracking of detailed individual preferences.
Also as mentioned, if I search for "thai restaurant" (which is written exactly the same in Norwegian as in English), the chances are very high I want a local thai restaurant in my city and not one on the other side of the planet.
Even if I enable location in DDG the search results includes a bunch of thai restaurants in Asia and the US. The map insert however is pretty spot on however, so all is not lost.