What is the consequence for not paying the train fare?

If the CTA police or a conductor catch you, you will be escorted off the train and the station. In aggravated cases, or if they are in a nasty mood, they can arrest you.

Cta Train Fare

There is no consequence for not paying the train fare.

As soon as you find out the turnstile does not move when the fare is not paid, there is no consequence to just walk back and leave.

Now, if you jumped or hoped or crawled under the turnstile...

Besides turnstiles, there are also the rotating doors with the bars that can only make a counter-clockwise turn. It's theoretically impossible for a human to go through when the fare is not paid. You can't crawl under it and you're not small enough to slide through it.

You'll most likely be arrested.

Seriously what is the point in not paying? It's $2.25 a ride or $5.75 for a day pass. I mean seriously pay up.

It will most likely result in you having a lower IQ, which isn't actually possible at this point.