terms & conditions of Sify

With the 150MB data limit, there is also another catch that nobody knows. If you carefully read the terms & conditions of Sify. It says that if you are using the net for more than 6hrs then you will not be considered as home user and considered as commercial purpose. Hope you understand what commercial purpose mean. There will be higher tariff for commercial users.
When TRAI has mensioned that Broadband means min.256KBPS of speed and 24X7 online connection. How can these stupids can limit that to 6hrs, 150MB per day.