And what you're saying is if you don't get invited to keys then the system must have flaws. See how that goes both ways?

Maybe, just maybe, you don't understand how to use the system to your advantage. Its not like people with high score somehow have it differently than you. No one magically got invited to keys while you didn't, we're all on a level playing field and you just haven't figured it out yet. This might sound petty or mean to you but its the reality and if you can't accept that then you won't enjoy pushing keys until blizzard makes some changes. Is that unfair? Perhaps. In the meantime try to learn something and maybe you'll see that the cards aren't as stacked against you as it may seem.