That’s odd – they never married.
Oh wait, Stu and Astrid did marry. Sorry.
I just checked my marriage licence -It said nothing about having to wear the ring.
My dad was a welder and never wore a wedding ring for safety reasons – in fact he had a long list of extremely gory stories about men who wore rings and lost their fingers in various nasty industrial accidents. My folks have been married for 45 years and he’s about the most thouroughly married guy I ever met. So I’d have to say that the OP’s friend is somewhat off-base.
BTW, according to my folks, when they were married single-ring ceremonies were much more common than double-ring. Of course, they ran in blue-collar circles back in those days, with most of the men working manual labor type jobs with the same safety concerns as my dad had. Possibly white collar men were more likely to wear wedding rings even 50 years ago. Certainly in old etiquette books you see mention of both double- and single-ring ceremonies, while modern etiquette books seem only to mention the double-ring version. On a wedding message board a few months ago there was a bride whose future husband didn’t want to wear a ring. The bride was concerned about “corrupting” the ceremony to reflect this. She was surprised to hear that the single-ring variation already existed and wasn’t at all “incorrect.”.
Jess
After I split up with my ex, I still wore my engagement ring for a long time.
While it didn’t stop me getting hit on, it did offer a nice easy way to end the conversation.
I if ever get married, I’ll wear the ring, because it would make me proud, regardless of what anyone else thought. (Although I don’t wear any other jewelry).
If he want’s to wear a ring that’s up to him.
As other people have said, and as I’ve experienced, a piece of metal on your finger does not stop people trying to hit on you, and niether does it stop you cheating if that’s what you’re gonna do.
There may have been reasons why the guy in the op was not wearing a ring, manual labour, resizing, alergies, or (as a friend of mine has) a phobia of jewelry, or he just doesn’t wear it.
Maybe your friend was disappointed because when she saw he had no ring she thought he was fair game, and was upset at finding out that she was wrong?
To answer your question, “Should married people wear a ring in public?”, my answer is “Only if they want to”.
I wear my wedding ring because it is a symbol of my relationship with my husband. It reminds me that my husband has promised to love and cherish me. I can look at my ring and get that warm fuzzy feeling of the love I share with my husband. He wears his ring for the same reason. It is not used as an advertisement to the world that I am married. To require people to wear a wedding band to let others know they are married is a silly idea.
My parents loved to watch The Love Boat and for some reason, the only episode I remember is one where a single woman pretends to be married by wearing a ring and a married man pretends to be single by removing his. Poignant hijinks ensue and they learn a valuable lesson (and don’t end up together!) Pamela Sue Martin & Gil Gerard, maybe?
Anyway, I feel completely naked without my ring. Except for baths/showers, I always have it on, although my wife sometimes removes hers when it’s cold outside.
My folks have been married for…lemme see…31 years now. Mom generally wears her wedding & engagement rings, Dad never has. He once told me that he wore it until they returned from the honeymoon, but then it went into a jewelry box, where it’s been residing all these years. Mom never cared one way or the other.
Dad gets hit on sometimes, & he casually mentions his wife in the course of conversation. How do I know? He mentions it in his “how my day went” summaries when he gets home. Mom just laughs. 
Heck, I get hit on even though I wear a wedding band. (And no, I don’t man by poly people.) Not often, but it happens.
I guess since it’s just a plain white-gold band, and I don’t have an engagement ring, it doesn’t look very wedding-bandy.
The hubby wears his, but it wouldn’t bother me if he didn’t, though I think if he quit wearing it, I would, too. Not out of spite, or anything, just because it seems more like a brand on a heifer (or a steer) if it’s not reciprocal.
This is how I feel about traditional engagement rings, and it’s why I never wanted one. (My husband and I got matching silver bands for engagement rings.)
Married ring-wearing guy here. I’ll echo what SHAKES and lolagranola said: I get flirted with a lot more now that I’m displaying a ring than before. Make of that what you will.
My mother’s family belongs to a denomination that is strongly anti-jewelry. They can cite the passage in the NT from memory. Hence no wedding rings at all. Men or women. This attitude sunk into me and hence I don’t wear jewelry of any kind (including wrist watch) though I am not a member.
Assuming absence of ring = single is just plain stupid.
I’m a woman who does not like to wear rings, and I wonder how that will go over with the man I marry.
I agree with the other posters that wearing a ring is no guarantee of faithfulness, and not wearing one is no indicator of infidelity. After all, if your spouse is going to cheat, a ring worn or unworn wouldn’t make a bit of difference.
The ring thing is a red herring. I think that someone who makes a big deal over a spouse not wearing a ring is just woefully insecure about the relationship. It’s the insecurity that needs to be addressed. Otherwise, I can wear a ring to satisfy my spouse, only to have him become suspicious of something else.
As for being able to tell whether someone is married, you really do have to ASK. I suspect that a lot of married folks who are on the prowl, and those with whom they would cheat, prefer the “don’t ask, don’t tell” policy. I can’t tell you how many of my single-gal friends have excused their liaisons with married men by saying, “But he wasn’t wearing a ring!” or “I didn’t know he was married.” Not asking gives them the option of saying they didn’t know.
And these same women, upon getting married themselves, are whining because when the hubby doesn’t wear the ring. But is the ring really the issue? Nope. It’s just that having been “the other woman,” they now have to worry about being cheated on.