I only smile because I'm too lazy to frown. It actually varies a little depending on the expression, but it can take as many as 26 muscles to smile and as many as 60 to frown. Therefore, yes it does take less energy to be polite.
I never said airlines don't ask, I said they don't always ask. As for immigration asking, there is a reason I put that in my comment. And "!!!"? Calm down. Not sure why you are so upset. Check this chart for future exclamation mark usage: "Actually, there isn't any proof behind this old saying. Scientists have studied the muscles needed for both facial expressions, and to do a small smile generally uses 10 muscles; a small frown uses 6. On average, a smile uses 12 and a frown 11. However, since humans tend to smile a lot, these muscles are stronger." www.sciencemadesimple.co.uk/curriculum-blogs/biology-blogs/muscles ....unless you are like this guy: You can tell he really struggles to smile in any picture of him doing it. It almost looks painful for him to smile.
So if you had to lift a car out of a ditch, would it be easier with 26 "musclemen" or with 60 "musclemen". When you have the answer to that you will know why it is easier to frown than smile.
If your onward or return ticket is with the same airline, the agent does not need to ask. She sees it on her computer.
I think a pretty girl with a smile could get her car out of the ditch much easier than you or I, smiling or not.
I remember, back in the 80's, flying into Lagos, Nigeria (for the 3rd time , so I had some idea what to expect) - IO " You have no visa sir!" Self "Yes I have a visa, it was issued in London. IO "I cannot see your visa sir" Self (sliding $10 note over the counter) "Can you check again, I know there is a visa" IO "Ah yes sir, now I see your visa" They have cleaned it up a lot since then.
I was more thinking of hormones released during anger and the consequent stress they impose upon the body's organs and tissues. Also, mental activity can be sometimes as tiring as physical exertion - I know this really needs to be defined in empirical terms to be valid, but I am sure we have all had some experience of it.
I'm 3 for 3 getting asked by airlines for a return ticket when departing USA. Perhaps it's due to my condition, resting b!!!!h face. Most likely due to to multiple air lines. I've never answered a single question from Philippine customs. I hold a finger to my ear, strain to smile then point my lips at asawa.
