Foregiveness? Reality of Tapping Towns During Holiday Event

I am in the same position as many here, will someone please explain the difference between a good neighborly tap and a bad one.

For example, if I go to a neighbors town and tap the Simpsons House, and other houses, does the house still appear tappable to other visitors?

I know the owner will have a friend "handshake" icon in their town, so do they have to clear the friend handshake before it becomes available to others?

Also, if I tap a high value house as a visitor, I get the same as a brown house as a reward, what does the town owner get more than if they just collected the $ sign above it?

I get the Tile bonus and have been farming that for a while, hence I leave a handshake in my town above squidport to allow others to gain the EXP bonus and for me to get an extra tile without having to wait. Do the Studio and Farm stack in the same way?

Thanks in advance