You were observing sun protective, re-enforced leather palms, and protective index and middle finger-guarded fishing gloves.
They are designed to defray cuts and abrasions when stripping flies, and provide extra support when fighting fish.
Yours, if wish to shell out out $14.95 per pair.
I'll take the war wounds any day...
If they were locals rather than visiting sports, they were more likely cheap cotton gloves from local marine supply stores. Commercial fishermen and cannery workers wear them all the time. Last time I checked they were $1.50 a pair or $12 a dozen. Work just as well, plus you can dump them in the washer between uses.