Automatic Parachutes

I was looking at my new-to-me glider on Saturday and noticed a 1" hole
just over the pilot's left shoulder with a red stripe painted above
it. See http://www.dg-flugzeugbau.de/grosse-piloten-e.html for a
picture of the hole.

We stood around and pondered what the hole was for. No one had much
of an idea. The manual was no help. I wrote to DG and they said it
was for the static line of an automatic parachute, which DG said are
very popular in Germany.

My question is, why aren't automatic parachutes popular in other
countries? I can understand the advantages. What are the
disadvantages (besides getting out of your glider when back on the
ground after a long flight and forgetting to unbuckle!)?

Also, how long is the static line?

Thanks, John DeRosa