I know of peopel who have honed an edge on the edge of a car window (roll it down, usually the edge isn't super smooth and is slightly abrasive). The trouble with using glass as a "steel" is that you'd probably end up scratchign it, and you'd have to be quite careful with it, as compared to a regular steel. I see no benefit that glass would give over a traditional steel. Now, normally with strops people use compounds on the strop, which actually cuts steel (Chromium Oxide is widely used). A leather strop backed on wood that is coated still flexes a bit, which is quite a different action tahn the bending/burnishing going on when steeling.
There is no ahrm in trying to "steel" or "strop" with glass, but I suspect you won't get any benefit over normal steels/strops. In fact, I suspect it would do a worse job.