I think what you're calling utilitarianism is typically called consequentialism. Utilitarianism usually connotes something like what Mill or Bentham had in mind - determine each individual's utility function, then contruct a global utility function that is the sum/average of the individuals. I say connotes because no matter how you define the term, this seems to be what people think when they hear it, so they bring up the tired old cached objections to Mill's utilitarianism that just don't apply to what we're typically talking about here.