Think about it. Both series take place in a world of death. Little Busters' Artificial World and Angel Beats' purgatory after life. Both series' feature a large cast where the male/female ratio is even, both series' have a long haired girl who likes cute things (Kurugaya/Shiina), both have an energetic pink-haired girl (Haruka/Yui), both series' have battles (Little Busters battles and the SSS rebelling against God), each series has a tsundere girl who wields a gun and go underground to defeat enemies (Saya/Yurripe). episode 2 of Angel Beats is definitely an episodic revision of Saya's route. Both series' has an episode that revolves around baseball. In both series, all the characters end up in the world of death due to a bus accident (Little Busters) and a train accident (Angel Beats) and they all must evenutally leave the world's of the dead by overcoming their regrets in life. Just compare Riki's goodbye to Kyousuke in Refrain and Otonashi's goodbye to Kanade at the end of Episode 13 of Angel Beats and compare the similarities. One can possibly see Angel Beats as a more developed Little Busters story because the characters are aware that they are dead. Yet at the same time, Angel Beats is more rushed than Little Busters. If Angel Beats got 26 episodes like it was planned, perhaps we can see an epilogue where the whole SSS reunite in the real world, reincarnated like Little Busters' ending. The only thing Angel Beats has that Little Busters does not is an All-Girl's Band.
We know that Haruka has issues with her memory, which lead to her contradicting herself and her parents, NPCs created from Haruka's memory for the dream world, contradicting each other throughout her route, because she's been messed with and accused of things a lot and had to break down and apologize for them. In Haruka's route, Kanata threatens to haul Haruka in for an "illicit sexual relationship" with Riki, even in the original all-ages game, as an Abomination Accusation Attack in a school that would actually see "teenagers have sex on their own time" as a punishable offence, and the disciplinary committee also sees Haruka with a lost child and they actually think it's hers. These kinds of accusations would have messed with her head enough that she doubted that she hadn't slept with Riki, so the scenes were added into her version of events after the fact — much like they were added into the game in an Updated Re-release.
She was in a different class from the majority of the cast, but unlike Haruka and Kyousuke, did not sneak onto the bus with Riki's class that ended up crashing. Her route in the Ecstasy expansion takes place after the events of Refrain, meaning it couldn't take place inside Kyousuke's dream world. Considering Komari is her roommate, this sets up the possibility that an NPC of her was created from the memories of people who knew her to make Kyousuke's fake world seem more real to Riki and Rin.
The reason the artificial world was created in the first place was for Riki and Rin to accept the deaths of everyone else from the bus accident so they could move on. Kanata would be in a similar position as them, struggling to move on from Haruka's death. When you consider her family was trying to enforce a hatred between the two of them, that same family would likely jump for joy at the news of the "black sheep's" death, and would try to encourage Kanata into seeing it as a good thing, thus giving Kanata a conflict between bottling up her emotions or mourning Haruka's death. If she were to pick the latter option, she would probably end up getting beaten by her family for doing so, given they were the ones who enforced that hatred. Furthermore, Saya's route proved that one didn't have to be among the students in the bus crash to enter the world Kyousuke built, so it's not out of line to imagine Kanata could enter the artificial world out of a desire to repair her relationship with Haruka and properly grieve without being scolded or beaten by her family for doing so.
