A: Oh, it's rude all right. What's next, putting up a small fence on a particular section of the beach so no one else can build a sandcastle there but you? (Although, hmmm, I hope I haven't given the rude people any ideas.) I've heard the argument of "Well, if I'm willing to get up at the crack of dawn and go down there, it should be mine all day"—and I think that's hogwash.
Let's be clear: You can "save" a chair for 10-15 minutes, max. That should be plenty of time to fetch the trashy novel you forgot in your room, get another daiquiri, etc. If you need more time, take your stuff with you and let someone else have the seat.
Hotel and cruise staffs need to step up and do their part with signage and actually enforce the seating rules.
Q: What's the etiquette for wearing perfume or cologne on a flight?
A: Nothing you bring on an airplane—including yourself—should have any sort of odor. Soap yes (actually, soap yes, please). Reliving the '80s by dousing yourself in Opium or Giorgio, no. It's not like your seatmate can open a window at 30,000 feet to let in some fresh air! By all means bring the perfume… but put it on once you reach your destination.
Q: On my last flight, some guy behind me started complaining because I reclined my seat. Apparently he was in a seat that didn't recline and it made it hard for him to use his computer. Now, I'm sympathetic, but if I paid for the seat, don't I have the right to recline it?
A: Ah, the reclining seat turf war. Airplane designers, what on earth were you thinking? This is not a feature—it's a disaster. And it's not like leaning backwards a few degrees makes the seat feel any less like concrete. Spend the money on better seats, not on making them recline!
Reclining seats aren't going away anytime soon, though, so we'd all better come to some understanding about how to use them.