Why spend money on SSL?

[frank]

This is the reason you should invest money on SSL:
The primary reason why SSL is used is to keep sensitive information sent across the Internet encrypted so that only the intended recipient can access it. This is important because the information you send on the Internet is passed from computer to computer to get to the destination server.

Free SSL also does that job. Then why the need of investing money in it? You forget to answer the actual question of OP.