I think this question goes far beyond the game. Alicia and Kat were in an alliance where they knew not everyone could sit at FTC. Even though Kat was voted out before the last member of outside the alliance, there seemed to be relatively legitimate conflicts within the group that allowed that to happen. The real difference comes with people like Troyzan, who did feel betrayed by Kim and didn’t vote for her to win. They seem to have made up because it was clear that nothing that had happened was out of malice. It is true that the game was a bit different during All-Stars, and though even then Rob did have relatively positive relationships with Jenna and Rupert, his gameplay was always driven by malice. He even says in Redemption Island that his goal is to get his alliance to hate the outsiders. I think Grant felt more betrayed because of Rob’s system where the in-group is supposed to hate the out-group. Even though it’s clear that not everyone could have made FTC, Rob’s system of play was designed to make it everything extremely personal. When he was voted out, he had no reason not to hate Rob as much as anyone outside of his alliance did. On top of him being generally less kind, at least in confessionals, his system of play relied on liking certain people more than others, whereas Kim seemed to have a mindset of liking everyone, but having to vote people out because of the nature of Survivor. I would also bet that she tried to be friends with people after the game more so than Rob