This is an issue I always think about too!
Yeh on the one hand its great, it shows you have something about yourself, your clever, and you achieve what a lot of others can't. But then on the other hand they may fear you'll walk.
I've been going for all types of jobs recently. One was to work for a company in the motor industry. I didn't mention holding an fATPL, just that I have a PPL in case they think I'll walk out for a high paid job. I worked in a crap job part time throughout my training, which I took around 3 years doing, and now when asked at interview's why I want this career change they all seem to think I'd be better staying where I am and working my way up. Thats opposed to letting them know it was only a 'stop-gap' job and that I'm highly skilled and fairly clever as I hold an commercial license!
Catch 22!