Do you ever have to break it to someone that life isn't fair?

There's been some things happen in our office that aren't exactly equal among the employees (mostly regarding raises and their timing) and a couple of people are being quite vocal and annoying about how "it isn't fair". I will say that I am in the same boat as that group but thankfully my dad and grandpa raised me from a very young age that anyone whoever tried to tell me life was fair was doing me a great disservice. Sometimes I catch myself about to say it about something that's bothering me but then I realize that sometimes, things just aren't fair, and I move on and I feel like it's in general made me a much happier person. Sometimes life breaks a different way and you just need to keep working harder and eventually it will break in your favor and against someone else. But wringing your hands and complaining to the world does nothing. I'll probably have kids within the next 5-10 years and this will be one of the lessons I try and put an emphasis on.