>>716262656
Because Wesker's goal was basically
>contain the outbreak
>retrieve samples from Arklay laboratory
>kill witnesses/STARS to finalize coverup
>Bonus: Combat Data
Everybody in STARS had to die.

Arguably like Rebecca going from RE0 to RE1, the fact that he had been running and fighting for his life for 24 hours at least sort of excuses being taken out by a cannon fodder zombie right as he got to the Spencer mansion