It could also be due to a misunderstanding. Perhaps there was an incident where the Weasleys' actions were misinterpreted by Hermione. Like if they accidentally made her look bad in front of the whole school during a magical event, and she holds a grudge from that.
One possible reason could be jealousy. Maybe she sees the Weasleys as getting things too easily in the wizarding world compared to her own hard - earned achievements. For example, they have a big family support system that she lacks, and she might envy that.
Perhaps in this fanfic, the Weasleys have some actions that conflict with Harry and Hermione's values. For example, if the Weasleys were to make a deal with a dark wizard for the sake of their family's safety and Harry and Hermione found out. This could lead to a rift and hatred. Also, it could be related to a love triangle situation in a very convoluted way. Maybe one of the Weasleys unknowingly gets in the way of Harry and Hermione's relationship, or vice versa, which causes animosity.
It could be a way for writers to show their creativity. By taking a well - known relationship and flipping it on its head, they can create unique and unexpected storylines. Maybe they want to explore how Ron would react to Hermione's hatred and how it would change his character development. Also, some fans might have their own personal interpretations of the characters that deviate from the original, leading them to write such fanfiction.
One possible reason could be a misunderstanding. Maybe there was a miscommunication about something important, like a plan to fight against the Dark Arts. For example, if the Weasleys accidentally left Hermione out of a crucial part of the plan, she might be very angry.
Perhaps in this fanfiction, her parents have some secrets that Hermione discovers. These secrets could be related to the wizarding world and their connection to it. Their attempts to hide these things from her make her feel betrayed and thus lead to her hatred. For instance, if they knew about some dark magic in their family history but kept it from her.
It could be that in the fanfic's plot, the Weasleys have some actions that go against Hermione's principles. Say, they might be involved in some pranks that have negative consequences for Hermione's studies or personal goals, and that's why she hates them.
Maybe in that fanfic, there are misunderstandings between Harry and the Weasleys. For example, they might have had an argument over something like magic use or family values that led Harry to dislike them.
In this fanfiction, perhaps there's some miscommunication. Maybe the Weasleys' boisterous nature is misconstrued by Harry. For example, their large family dynamic might be overwhelming to him at times, which could be a reason for the 'hate' in the fanfic.
One reason could be a divergence from the original character traits. In the original story, Hermione and Ron have a complex relationship with love and friendship. Fanfiction that misrepresents Hermione's feelings towards Ron might go against the essence of her character. Maybe the fanfiction portrays her as hating Ron in a way that doesn't fit with her growth and development in the official series.
I'm not sure if it's popular. It depends on various factors like how well - written it is, how unique the concept is within the large Harry Potter fanfiction community, and how much it gets promoted. There are so many fanfictions out there that it can be hard for any one to stand out.
One possible reason could be jealousy. Maybe one of the Weasleys develops romantic feelings for Hermione and the others don't approve or also have feelings for her. Another reason might be related to her magical abilities. If Hermione has some unique magic or knowledge that the Weasleys think can benefit them or their family in different ways, they could fight over it. For example, her knowledge of ancient spells could be seen as a great asset.