Honestly, I was expecting this would be about setsuna's bday, since it's been just over a year since they got married and now her mother wants to get back into her life... And she thought it important enough to tranq him, instead of just talking to him normally, like she usually does. Seriously, she has no issue talking to him when setsuna's not around, could've just had a chat while he's shopping. I know it's a comedic manga, but there's absolutely no reason for mom to "kidnap" him. And she's very capable of bringing up riches out in the public too, it's an established fact.