I didn’t know you could give villagers on foreign islands anything...
This isn't possible is it? I've been to my friends islands plenty of times and I've never gotten that option. And yes, I would absolutely consider it rude. Treat the villagers like they're part of the island. If someone doesn't want you running over flowers, don't do it. If someone doesn't want you talking to villagers or giving them stuff, don't do it.