I work in IT. Most systems have laughable security. Passwords are often saved in plain text in scripts or config files. I went to a site to help out a very large provincial governmental organization move some data out of one system and into another. They sat me down with a loaner laptop and the guy logged me into his user account on the server. When I asked for escalated privileges, he told me he'd go get someone who knew the service account passwords.
After a few minutes, I started poking around on my own... And had administrative access within an hour. I could read the database (raw data), access documents, start and stop the software, plus, figured out how to get into the upstream system that fed data to this server... I was working on figuring out the software's admin password when the guy came back. I'm sure that given some more time, I could have rooted the box because the OS hadn't been updated in years.
SMS messages are crammed into the messages your phone exchanges during 'pings' to register with the local cell tower. It literally costs the telco nothing to exchange texts between subscribers on the same network, and as far as I know, telcos don't charge each other for exchanging SMS messages, because the cost of tracking it all exceeds the practically zero cost of just forwarding the message.