The screaming you hear is coming from execs at the global cellcos. For years we have been hearing how voice will be free. (Hasn't happened yet, but it has flat rated.) Now it seems the text messaging revenue arm is decreasing - 9% from last year globally.
According to this article, "Pinger and an explosion of smartphone messaging services -- like iMessage, BlackBerry Messenger, WhatsApp, Viber Media, Facebook Messenger and KakaoTalk -- have managed in just a few years to slash away at the important revenue that cell phone companies get from text messaging. Analysts say there's no end in sight to the financial blood letting."
This explains all the metering and bandwidth caps. Revenue is flat for cellular so they need to make it up in data revenue. When you are spending $7-9 Billion per year on the network, plus paying for roaming and having to buy spectrum, you want ARPU and revenue to go up.
There is also all this envy to Apple, Google and other cloud companies that are making money from apps, shopping and usage that the cellcos are not getting a piece of.
I think it is also why a good many cell phones do not have wi-fi. That tends to work two ways though: wi-fi is capacity offload while the customer is still paying you a monthly rate. Wi-fi upload may be how they save some money on capacity upgrades. Wi-fi capability in teh handset would also be a way to appease the folks who get throttled or capped. However, that doesn't help the carrier revenues. They just don't want to be a dump pipe, but every move they make seems dumb.