@ Cecilia
I know what you mean (not saying I'm a paid artist, but I've done a few traces that were paid for, and some medical posters that were paid for). Edit: and a fizzy drink label.
Somebody once approached me to a logo for them (it was going to be printed at A4) and I sat with the dude and designed something. He said could he show it to his boss and they would make a decision because there was another logo they were considering.
"Sure" I said.
And I printed them a B&W logo to scale, and then reduced the colour raytraced logo to about 200 x 200 and saved that as a medium-quality jpeg on a disk for them. I said "phone me if you want me to go ahead."
Anyway the next day I got a call saying sorry, they couldn't use that logo, they were going to use another person's offering. I said cool beans, cheers.
However...the next week I got a call from a production house. An irate guy wanted to know what I was thinking giving my client a 200x 200 image that was to be printed at A4..
:-o
That conversation was very short and I never dealt with that individual again (the one who tried to steal my logo).