Peter Burgess said:
And what about amateur self-publishers (individual or society)? Caving clubs who publish stuff? Illustrated caving journals?
All of these examples are completely different kettles of fish to a publishing company like, in this case, Crowood.
The Complete Caving Manual is being commercially published, and it is obviously worth Crowood's while to produce it since they've gone to full-colour repro, so they're not doing it as a charitable act to the caving community. They will have worked out a budget for the publication of the book to include Andy's fees, repro, printing, binding, distribution and so on. That budget includes the princely sum of ?0.00 for photographs because they are confident that they can exploit the talents of many well-travelled and creative cave photographers who will be willing provide them with great pictures for nothing.
Remember, kids...Just Say No.