Some of the replies here are truly uninspiring contrary to the title of this thread.

You are always within gliding distance of some landing spot. There is a true psychological barrier preventing new students from understanding this concept unless you have helped them to overcome this. They think that the home airport is the ONLY landing spot. Yes, some will do cross-country once and then never again. That's OK. At least they will have the experience to properly size up real landing spots along the way.

But many more will be grateful to you in the realization that the anxiety to never leave home base was all in their head. This is where real inspiration is born.

If you don't do this with them in practice, you are doing your students a tremendous disservice. Unfamiliarity is dangerous, and can lead to disaster. There is a reason why student airplane pilots are taught to practice instrument flying for emergencies - because they will eventually encounter VFR flying into IMC. It will save their life.

The same applies to practice cross-country soaring.

At the very least, the glider instructor should fly with the student to an unfamiliar airport and use that as an out landing spot. Or better yet, pick out three unfamiliar airports and do it. Teach them everything they need to do to size up the landing as if it were off-airport, like it is described in the Glider Flying Handbook.

Doing your first out landing alone (even close to your airport) after getting your Private ticket is exactly the wrong time to be experiencing it for the first time.