Treehouse of Horror Ultimate Tapping Guide

Sorry if this has been answered elsewhere, I've poked around and haven't seen it posted. Is there a benefit (other than the 4 probes instead of 2) when a Gremalien goes unnoticed in a Neighbor's town? I've been waiting until I go to bed to drop them, but now I realize that my good Neighbors don't even know it was me unless they tap them. Is the 15 points only for tapping them in your SF, or is it for each egg dropped as well, and 15 points whether detected or not?

I'm hovering between 8 & 12 on my leaderboard, but I know that's just for bragging rights. I'm above par on my probe count (for now), and I want to help my Neighborinos as well.

For now, I'm off to drop my 27 eggs for the night and will check back tomorrow.