One thing we discuss at length in Meditation Teacher Training(which you should take!!! — smile) is all the misconceptions about meditation which are afloat out there in the world today.
One major one is the confusion between deep relaxation in Savasana and true meditation, which should be done in a seated position with the spine erect. Many people out there teach "meditation" in a supine position. This really is leading people in the wrong way. Deep relaxation is great, but it is NOT meditation. Certainly it is easier to lie down than sit up straight, and I suspect that this is why it is sometimes taught this way.