Given how much the world has already noticed that instant messaging can be cheaper than SMS, it’s surprising to see the founder of WhatsApp trying to persuade carriers that he’s actually doing them a favor. In an interview with Reuters, Brian Acton said that his messaging service is “facilitating a broad movement to data plans,” from which carriers “stand to benefit quite substantially.” While it’s certainly true that smartphones and data plans make nice margins for operators, Acton’s thesis also slithers around some slightly inconvenient evidence. According to analysts at Ovum, carriers lost $13.9 billion in SMS revenues last year, and are set to lose another $23 billion this year. All the while, WhatsApp’s traffic is growing rapidly, with total messages doubling from one billion in October 2011 to two billion in February. With data costs falling around the world, and with platforms like WhatsApp running on lower-priced handsets (such as those running Nokia S40), it’s the consumer, not the carrier, who ought to be charmed.