There's obviously not a history of tee shots causing serious accidents on the nearby roadway. I guess it takes someone having to suffer from such an avoidable incident before the course reacts accordingly. The question in that situation is obviously why wait until that possibility is realized?
Hybridwood, you submitted an unbiased and respectful inquiry to the club highlighting those possibilities. Unfortunately, however, I seriously doubt that they will act on it until something serious happens.
Nevertheless, you did your part.
I'm guessing that the road there was present long before the golf course was. It would seem, for the greater good of public safety, that they would spend a few thousand dollars to help prevent a serious accident from happening. But unfortunately some of these courses don't react unless they're forced to.
And in the rare instance that the golf course was there prior to the road being developed, then it's on the city. In either circumstance, it just seems like a completely avoidable situation. Someone (either the course or the city (maybe both) ) would be well served to compromise on a reasonable resolution.