My old man was sort of "bah humbug" about it all. He wasn't necessarily "surprised" that my mom would do such a thing, but still "surprised" — eyes wide open, shaking-of-the-head.
My mom was notoriously sneaky, though her legend is prototypically more tame than this: "oh look at this cat I found on the sidewalk that was lost!", or "this dog was going to be put down if someone didn't take it."
My favorite story though is that when they (my mom/dad) went on a week-long canoe trip: your pack is usually heavy when you start and is supposed to get lighter as you go — you know, from the food you eat. Well, my dad noticed his was not getting any lighter as the trip went on. Fast-forward a few weeks, my mom is out working in the yard and my dad goes out to get something when he notices some really particular rocks that match at all with the existing rocks that were laid.
Little did he know he carried in his pack during their canoe trip.
The rest of the day (I broke the news to him shortly after lunch hour) we spent the day chuckling about "how 'Jeanine' it is [of a situation]" — Jeanine being my mother. We found common ground there if nothing else.