| | Re: Latest OS: 9930 220.127.116.117/18.104.22.168 (All Languages)
It's called "breakage".
There is an inherent cost for the networks for everything they offer to the user. Data for example - if they sell you a 6GB plan, they know by averages, that the average usage may be 1 GB/month/user. I'm using arbitrary numbers here -
When users add a feature like tethering, or WiFi hotspot, the carriers know that it will increase their costs, because the "breakage" is now higher, meaning more data will get used on average. Breakage would be the term they'd use when they are betting on usage, and make no mistake, this is all about odds.
If they believe usage to be X without HotSpot's and it goes to X +90% with a HotSpot, they make less. Think of it as an insurance policy. The underwriters are placing odds on the fact that you won't need to use them. It's all about risk management.
In the very same way - the carriers are betting you'll only use 1GB of data, but you bought and paid for 6GB. They make their money. With a HotSpot, you'll use say 3GB, forcing costs higher for the carrier. They make less money.
They charge, because a) they can b) they do incur a higher cost when adding a feature that will incur more usage.
In the end, to the carrier, 6GB of mobile date isn't the same as 6GB of tethered data, since usage (breakage) will be far higher on the tethered data.
At least 17+ different BB's since 1999 -- too many to list...