It is upsetting to some because some people assume a resource can't have feelings. Like saying "women are objects." Obviously this isn't what is meant with Human Resources but in today's world people want to argue over naming conventions as if their perspective of a name or even a definition is the only right one because it fits their goal. Make no mistake if you called Human Resources instead Team Builders someone would eventually a few years down the road get mad because you can only build buildings with objects and so the name doesn't do justice to the feelings of people again.