Last time I checked, gliders need tow planes. Do you know another way that I do not know?
Yes, i do.
A winch.
A long cable, stretching from one end of the strip to the other, hooked to the glider. A winch that starts reeling in that cable, towing the glider along the strip at speed.
You'll be amazed how quick they get up in the air that way. Very steep too.
They unclip the cable when level, and a small parachute attached to it makes it fall down a bit gentler as it otherwise would.
Using a motor plane to pull them up requires somewhat of a 'grown-up' airfield, with all bells and whistles. The local club can't afford to run such a thing. They can't afford a tow plane either, and have been winching gliders up since the 1930s.
They can't get up very high, need to gain altitude by doing what the sport entails: find and use thermals.
And that cable has to be towed back to where the planes are waiting to go up after every launch.
But it works fine.
Yet, they were grounded...
P.S.
Obvious that i didn't read on and see resummerfield's answer, isn't it?

Sorry for the redundancy.