That's part of the strategy. The most eyeballs see it right after it's released, and the intended effect is created. They've been doing this for quite some time. The first experiments were with using different headlines for the same story in the online and print edition. Generally the print edition headlines are the most restrained.
I don't know the intended goal. It might just be clicks or page views, but what typically happens is:
- Article launches with sensational, buzzfeed quality linkbait headline.
- Article gets lots of clicks
- The title is quietly changed to a more restrained version which often matches the print edition title.
At first I thought there must just be different editors overseeing the web and print editions, but now I think it's an intentional form of viral marketing or activist editing.
In some cases, the sensational headlines really diminish the journalistic quality/seriousness of the article, or create the impression that a minor point in the article was the main thrust of the article.
Similarly, there has occasionally been a headline that appears intentionally boring so that the paper can publish a story but effectively hide it from view.
So in a nutshell it's classic misdirection, enabled by the digital medium, since tracks can be fairly easily covered making it harder for those who care/notice to call attention to it. For a while I thought about creating a screenshot archive of changed titles but eventually just stopped reading the paper.