Treasure Maps

Does the location that you gather the treasure maps from have anything to do with the rewards that you receive from them?

I gather Toadskin and Boarskin maps from Botany and for a while I was gathering them from Middle La Noscea and I would get varying rewards (anywhere from 5-10 myth). A little while back I switched to Eastern La Noscea and every map that I have gathered there has only given me 5 myth. One day I gathered one from Southern Thanalan and it gave me 7 myth. Next few days, back to Eastern La Noscea and only 5 myth per map.

Am I just experiencing weird RNG or does the location make a difference?

It's all luck.

The tome payout is determined by map type and nothing else. Toadskins give 5 myth, with the occasional triple reward map that gives 15 myth. Boarskins give either 7 myth or 3 soldiery, with the occasional triple reward map that gives 21 myth or 9 soldiery.