Some journalism experience here.
The number one reason the headline was written like that was because newspapers have a style that they tend to follow religiously. A consistent style makes the paper more readable; regular readers become accustomed to it, and a style change can be quite jarring.
Most newspapers follow a common style to a large extent. A common source for style rules is the Associated Press Stylebook.
The consistent use of present tense in headlines and cutlines gives a sense of immediacy, as mentioned, and actually does eliminate confusion in many cases, especially since it’s what readers are accustomed to.
Additionally, headline writing is kind of a pain. You’ve got a small space to attract attention to the story and convey the actual meaning of the story, and again, there are certain style rules that should be followed. Example: You can’t write a headline that says:
You’d have to go with something like:
President to Sign
If there’s more than one line to the headline, the lines have to be close to the same length to look nice.
Generally, you can cram more into a headline with present tense than with past tense: “spurs” takes less room than “spurred”.
I agree that “Close call in the mountains spurs local man to produce high-quality maps” would have been better stated “Close call in the mountains spurred local man to produce high-quality maps.” Most likely the person who wrote the headline was working under a deadline and just didn’t think about changing the style. It takes a lot of headlines to make a newspaper, and quite frequently they get slapped out as quickly as possible, especially in the back pages.