Not using a throwaway but isn't there a difference between forking a public Github repository without attribution and stealing industrial secrets encrypted into photographs?
Yes, there is a difference, but that's because academia is not industry. Since academia's main goal is to publicize findings rather than keep them secret, plagiarism is the academic analogue of stealing "industrial secrets" and then giving them to a competitor (i.e., increasing the prestige of a rival university).
The overall effect is comparable, even if the currency (reputation instead of money) is different, and the decision to steal is still rooted in the same sense of ethics / morality.
As an addendum, it should be noted that reputation and money are not unrelated, and that when stealing ideas from other labs and taking credit for them, scientists are effectively putting on a false show for funders that can increase their ability to get grants.
The overall effect is comparable, even if the currency (reputation instead of money) is different, and the decision to steal is still rooted in the same sense of ethics / morality.