Text Messaging With Phones

I was recently text messaged on my phone by a person on a phone. I saw no logic in this whatsoever. Text messaging on a phone is pointless, why text message when you can call them and talk to them. "But what if you can't call them like when you're in class or something" some have said, hogwash! I say. Maybe a message such as "my knee is sticking out of my leg." or "a guy in a black mask is threatening me with a knife and/or gun." could be acceptable but something like "Hi!" or "What are you doing?" defeats the purpose of a phone. Why not go back to the good 'ol days of note passing or here's a new one Wait until class or whatever ends. I doubt it's worth the nickle or whatever you spend to send/receive a text message just to say Hi during english.