I see no harm done, really. I politely decline. I do get the same person trying to recruit with the same macro message every day I happen to pass by them, but it doesn't bother me. FCs can be struggling to get new people, and Sprouts are too shy or don't know to ask to join one. We're all doing our best to play the game how we like, offense shouldn't be taken so much unless it's blatant harassment.