The term "software developer" works for me. :)

It's not a problem only with programming jobs. There are plenty of occupations that people have as a career, but that other people can do on the side. I think the confusion comes up because people want to identify themselves as what they do at work, rather than who they actually are or what they actually do. For instance, people say "I am a programmer" more often than they say "I program".

Since people use that first form, I've often seen "title inflation". Some people want to sound more important than what they actually do. "Software engineer" is a fancy term for "code monkey". "Software Designer" seems to mean "code monkey without a spec to follow". You'll find a lot of "Dircectors of" in small business, although they aren't really directing anything more than anyone else. "Vice president" positions in the same company have inflated in numbers over the years too.

Furthermore, I don't think getting paid or having a job has anything to do with the level of conduct or the seriousness of the activity. The number of hours a person spends on the activity each week also doesn't have anything to do with those things. This is more apparent in the open source world where a lot of unpaid works goes on, often by "hobbyists". :) I think people use the word "professional" to divide those two groups and make the "hobbyists" seem somehow inferior because the "professional" goes to an office and sites in cubicle five days a week, and that somehow makes the activity more worthy.