Because everyone involved wants "stealing" to be the explanation? It's one of those geopolitical things where it's obvious lies wrapped in obvious lies but it doesn't matter that everyone knows that so long as no one who matters admits it formally. Like the US blowing up that pipeline: yes, it's abundantly obvious that they were the only ones with the means, motive, and opportunity to do it and every other possibility is absurd, but it doesn't matter as long as no one admits it because the issue fundamentally cannot be pressed further.