So they help employees, but it’s to a large degree self-serving (even if the HR person himself does not realize it — it’s why he doesn’t get in trouble for wasting time on it). But when it becomes actively detrimental to the company, always assume HR will make the decision in favor of the company.
Treating HR as generally hostile is also a bad idea — the assumption of hostility is often met with the same, and now both you and HR are acting slowly, carefully and inefficiently — but never assume they’ll always be your friends. They’re generally friendly, and they may even be considered friends, but ultimately their loyalty is not to you.
The same is true of really anyone in the company — your boss, your coworkers, your attorneys, etc. Their loyalties are always to themselves, and their families first (by which job preservation is a very strong incentive), and maybe you fall in line somewhere.
I think we agree on the role played by HR. You need to be aware they serve the organization first (as do we all). I just wanted to point out that in the day-to-day, they often provide real benefits to employees, which may be self-serving but there’s no rule that self-serving behavior can’t be mutually beneficial.
And to be honest I don't see myself doing anything different than that as well. It's going to be very unlikely I am picking a fight with my employer whatever you are coming to me with.
At the same time, HR does regularly help employees avail themselves of resources (communications with health insurers, 401k providers, etc.). So in that sense, they are "there" for employees.
As far as I can tell, HR does a few things:
1. promote the idea that the company is a great place at which to work (market the company to potential hires, tell current employees about all the great perks, downplay negatives or ignore them)
2. answer most general questions of current employees (benefits)
3. document statements given to and taken from employees (hiring them, firing them, workplace allegations, rules violations, etc.)
Most of it is designed to protect the company but some of it is sometimes the only way to get something if you're an employee. If you ask: "where should I go to set up my 401k?" or some variation, you are pointed to HR.