Why did the immigration officer take pictures of my passport with his personal phone?

The user, an American with a new non O-A visa, shares an experience at Bangkok's immigration where an officer took several pictures of their passport using a personal phone. The comments include various theories ranging from the officer possibly needing images for training purposes to light-hearted remarks about the user's appearance. Some users suggest it's normal and shouldn't be a cause for concern, while also providing information about visa stamping procedures.