You answered your question in the question
You actually OWN your work. Now you don't. At any time for whatever reason you can get a banned / can't login message because you broke certain guidelines whether you did or not.
Basically it's like working for yourself or someone else. All the traffic that comes to you through blogspot is just making blogger bigger. If you are just toying for fun and you're insanely cheap then don't bother.
If not spend less then you would on lunch one day and get your own site where you own your content and call the shots. Also if you ever one day plan on selling it... It's against the TOS to sell a blogspot I'm quite sure.
Play with a free one the minute you realize it's something you like go on and do your own thing.