And the meta-question of "why did the museum choose to waste money on lawyers that way" is "bureaucrat X decided that the scans belong to the museum, so no furt

And the meta-question of "why did the museum choose to waste money on lawyers that way" is "bureaucrat X decided that the scans belong to the museum, so no further logic or rational thinking will be applied unless absolutely forced to". That's a common property of all large institutions: the reasons why a decision is made may as well be arbitrary, but by golly will they stick to it and die on the hill, if they can.