Opposite Direction Landing Operations - Efficiency? Geography?

A question for all of you who fly various places around the US and world-

My question is regarding tow operations where launching/landing gliders use one runway end (likely, the end heading into the wind), and the landing towplane uses the opposing runway direction (likely, landing downwind.)

If you're at a club, field, or airport that routinely uses this type of operation-
1. Is it geography that drives this? (eg sloping terrain or obstacles)
2. Is it efficiency of operation? (eg, the towplane lands downwind and comes to a stop near the launch point, without having to taxi much.)
3. Is it some other reason?
4. In any case, do you have any procedures in place deconflict landing towplane and glider traffic, other than radio call awareness?
5. At what appx wind magnitude does the operation shift to all launches and landings all done in one direction - what is considered excessive tailwind for your towplane/operation?
6. Is using opposing landings a field policy, or does the operation let the towpilot/launch crew/glider pilots decide it on any given operating day ?
7. Any other comments or experiences you'd like to relate on opposing-landing operations?

Thanks for your insights.