Maybe there is some sort of weird radiation that has turned the people of Glass Hill into mutants and genetic disasters.
maybe Glass Hill was looted and pillaged a few years ago, leaving the population decimated and horror stricken.
Maybe they don't have good soil, so their crops are weak, leading to weak people, weak herd animals, and so on.
Maybe they are cursed. A warlock, angry at the people for not paying him tribute, has hurled a curse on them.
Maybe they are unfortunate because they have a halfling for a mayor.
Maybe they are unfortunate simply because they live in the remote backwater of Glass Hill, 100 miles from the nearest town. They are all backward hicks who don’t have a clue about recent events in the world.
Maybe they are unfortunate because the tradesmen who visit them always rip them off, but they are too backward and isolated to know the difference.
Maybe they are unfortunate because there is a band of humanoids in the area that keep kidnapping people from the town and doing unspeakable things to them.
Maybe their well water is polluted.
Maybe they all have bad teeth.
Maybe there is nothing unfortunate about them at all, its just the opinion and perspective of the person that told them that.
Maybe there used to be something unfortunate about them, but some other heroes have already saved them from their unfortunate fate.... and are now demanding a huge payoff from the people of Glass Hill.
Maybe Galss Hill sits on an ancient dimensional rift that must be resealed with a powerful spell once every 100 years. Now the book with the spell in it has gone missing and the 100 year time frame is almost up... the spell must be found and cast before the town is sucked into the abyss.