Symbiotic relationships can take various forms. There are forms where the relationship is only advantageous to one party and either damaging to one or does not affect the other party at all. But the way most of us think of symbiotic relationships is the kind called "mutualism" where both parties benefit from the relationship. This is like bees pollinating flowers, where the bees get nectar and pollen and the flowers get pollinated. Or the sharks getting their teeth cleaned by the little cleaner wrasses on Jacques Cousteau specials -- both parties benefit. Read more about symbiotic relationships and mutualism in particular on Wikipedia:
I believe that legal vendors and publishers have a mutually beneficial symbiotic relationship with librarians. I am not speaking of buying and selling, although that is certainly an important aspect. I am thinking of the product reviews and independent research that librarians perform for free on the products vendors and publishers produce. These are useful for marketing purposes, but far more important for product development. You have independent, highly trained, consumer-oriented testers examining your products. They are evaluating the publication or database for you; testing how user-friendly it is; comparing the quality of data, currency, and finding aids.
A really good published article doing an in-depth review and analysis of the workings of your database should be invaluable. While I can appreciate the amount of trepidation that the vendors and publishers may feel over such impending articles, and certainly have encountered and seen others run into attempts at spin and stone-walling, I hope the vendor/publisher CEOs realize that the insights in these articles can be pure gold for your development team. We are not "out to get" anybody. We want to improve the working of an already esteemed tool. Often, the article may include suggestions for improvements that might or might not have been thought of by your staff. And the level of confidence that an independent review inspires in the library community is (naturally) beyond price.
So, please, vendors, publishers, all, can we work together to improve and review products? We do not expect or want to have access to trade secrets. We are very grateful for the level of trust and access many of us have already been granted by many large vendors. I think it has been a good outcome. We have the same end in view: we want the best product for you.
This picture is actually a moray eel having its teeth cleaned by a cleaner wrasse. The image is from www.geocities.com/seasidepix, and has a signature on it.