You accept the card with a non-committal thanks. He probably disguises his investment proposal as a personal tour to unsuspecting tourists trapped in his car.
Surprisingly, he doesn't pursue the line of conversation about his business or a tour. If he's a salesman, he can't be that good if he didn't walk through that door.
Not that it matters as you have no intention of calling him. You're here on vacation to relax and enjoy time with your best friend.
When he stands to leave, you slip the card into the seat pocket. There's no point in keeping it with you. As long as he doesn't see, what's the harm?
You keep your eye out for him at the small baggage carousel with a ridiculous notion that he'll figure out what you've done. Does anyone ever ask for their business card back?
Either you lost him in the small crowd or he didn't have anything to claim. By the time you gather your luggage and turn your attention to finding the hotel shuttle, the man fades into memory.
His statement about the island's secrets lingers all the way to the hotel.