Unless your area of scholarship is at all textual, bibliographic, publishing, material culture of books or print media, or in any way historiographic – in all of these cases it is no longer optional or restricted to "special" cases: all these details become required for each and every entry.
which is really strange, since it's a completely useless information which varies from country to country
really? Distribution to movie theaters seems to be pretty international - I've certainly seen "Miramax" at the beginning of movies all over the world. For DVDs etc. this may vary, but then the distributor seems quiteimportant and equivalent to a book publisher - we'd want to know which version of a DVD is being cited/used.
Doesn't the cut of the film sometimes vary between distributors?