you don't need a rooster, but they are helpful if they don't get mean. they will always have an eye on the sky and for other dangers. they are helpful to the hens in finding food. they also round out the chicken social dynamics.
you don't need them, though. also, fertilized eggs are no different to eat the nonfertilized eggs. most people see a fleck of blood and assume it's a fertile egg, when that fleck of blood has nothing to do with fertilization (there are pictures on here of how to tell fert. vs unfert.). the chick doesn't even start to form until the hen starts sitting on them, and even if she was, a day isn't going to make a difference.
some here have purchased home capo kits, allowing you to do surgery and neuter your rooster. he will be different afterwards, and some have reported they sometimes go broody.
or, the last option : dinner table
