Whoever told you that most likely said "For the first 20 days..." because your data caps are refreshed hourly, if not daily during that period to ensure the system is working properly.
As for getting rid of data caps, imagine if you will there's infinite bandwidth in a space-based system. It's not like you can just fly someone up on the shuttle and do system expansion on a regular basis. Then imagine if they don't, and people complain that their system is oversold because everyone on that gateway is streaming Netflix at the same time, bringing the acceleration system to it's knees.
...This is why there are data caps.