A serious tender response is not a brochure. It contains your price, broken down further than you would ever volunteer. It contains your delivery methodology, which is the thing you actually sell. It contains named people with their real experience, your references, your assumptions, and your honest read on the risks in the project.
You assemble it over weeks, at real cost, and send it to an evaluation committee you have mostly never met, at an organisation that is simultaneously receiving the same depth of material from your competitors.
That is the arrangement, and it is not unreasonable. Buyers need comparable information to choose. The problem is not what you send. It is what happens to it afterwards.

