Perhaps, but it's an apocalypse situation. Not everyone will make it through without being infected. I have a plot I want to tell and would have difficulty pulling it off without a few meaningful sacrifices. Lust zombies are central to the plot. Plus, your looking at being infected in a negative light. It's actually another way to inject more adult scenes into RB.
Though, of course I'd understand if a player got attached to a certain side character and wanted her to be a core love interest and have happy endings all around. I want that too, but that's just not where the plot is headed. Crazy stuff is happening in this world I'm building.