An in-universe explanation of hobbit rings, courtesy of a superstitious hobbit.
#title:The Curse of the Tavern Ring
I cannot believe it, but I must, for it has happened. My dear Lily Banks has rejected my marriage proposal! 'Tis a shock indeed, as we've been good friends since we were children! No one knows her better than me!
And the ring I gave her? A beauty, it was! Straight from the finest tavern west of Buckland! The Bartender, knowin' I had done some good deeds 'round there, even gave me a fine deal for it, bless him.
There is no way that my sweet Lily could reject me! Me, the extraordinary Bongo Diggle! So there must be another reason she would do this.....
The ring is cursed! That must be it!
Perhaps some Big Folk made this ring in a far-off place, and intended to use this ring for mischief! Or perhaps some poor soul died before they were able to propose to their love with this ring, and haunts anyone who attempts to do the same!
I swear to my mum's grave, the hair on my toes will fall out before I buy another ring from that place. Bad luck, it is. Of course, seems like taverns are the only place you can find wedding rings these days....