I used to bicycle so much that I think for a while it defined me. However, I would not call myself a cyclist. A cyclist is one who does it and gets paid for it. I used to work at an electronics company and my title was "Systems Analyst." I could legitimately walk around and tell people I was a "Systems Analyst" because it was my job, I was paid for it.
If I bumped into someone who "taught" at an afterschool care place like "Little Soldier Afterschool Academy," and they called themselves a teacher, I would be offended. Why?
I owe more money for my education than I will be able to pay back before I die. I spent 8 years in college and took more tests than I can count to become a certified teacher. I think it demeans my efforts when someone who does not do something professionally to label themselves so that it appears they do. Normally, titles define what we do for a living.
A title such as astronomer should define not just who you are, but what you do to exist (to make ends meat-if you will; a career).
AT6RC, AT72ED, Orion ST80 (guide scope), Celestron 8, SW254N, Canon 450D, Meade DSI (guide cam), Celestron CGEM DX