My friend told me I need to learn morse code, radio theory, rules and
regulations in order to pass the Ham license test. Why can't I just operate
without a license? Who will know?

RB

Well, there are many pirate/fake call sign operators out there, but legit
operators may not want to talk to you if you can't give a valid call sign.
Also, in the rare case that the FCC catches you, they can lay a big fine on you
and block you from getting a license in the future.
I heard of some people who carry ham radios with no license aboard as a safety
item and to simply monitor. I'm sure someone has the specifics on all of this.

RB