Suspicions center in two areas- 1) Let's say you are an official and your brother coaches at School X. Game film isn't like legal discovery in court where the prosecutor has to turn over every scrap of evidence they have to the defense. Coach at School Y is nervous you may let brother at school X have access to what you have in your library. Locally, most schools have a policy that they will not share conference member game video with schools that are out of conference. This usually arises during the early rounds of the playoffs.
2) Coaches are perfectly happy for you to look at clips of what their opponents are doing illegally. They are not so keen as to watching and picking up tendencies of things they might be doing.
Correct. A concern may be they were willing to share game A with the other team, but not games B, C, and D. You know the other school is getting whatever video they want from someone on another team who has it.
We had some schools resist sharing video for this reason, but then we would get schools sharing another school's video to have someone look at a specific play for clarification.
We had a coach late in the season tell us they did not share because they did not have permission to share the OTHER team's video. How is that different than sharing it with another team? I explained the other coach had shared video all season so he was OK with it. We still didn't get his video.
Fortunately our crew received at least 1 video from every game this year. It has been a huge help for us to discuss scenarios and review our work. If most of the schools in your area are using it, you are crazy for not getting your own account. Even if you only have 100 members, the cost is only $8 per. I know crews that would get 15-20 guys together to buy an account and they felt it was worth every penny.