To the right of where you are talking as you face jump seat there are 2 bins under window. One nearest exit door has demo stuff in there - masks, life-jacket etc but the other one is usually free (and empty) and is not really accessible to 14 GH, so stays empty.

I use that.

Have had FAs chide me for even placing shoes under 14 either side, so it might be the rule.

Let me guess on the FA .. Asian with heavy rim glasses?