I work in a busy Emergency Department and frequently someone will need a pen momentarily. I often don't have enough time to explain and check if they know how to use a fountain pen. I will happily lend my pens (nice or not) to other people who usually carry FPs. However when it's hectic I simply don't have the time to make sure that people aren't misusing the pens so I always carry BP reinforcements.
When it's quieter I will happy lend out FPs with some guidance but unfortunately most people severely underestimate even the value of my FPs - cheap or expensive and I feel I wouldn't expect them to repair a nib or replace a pen that they didnt realise was worth even a meager $50. I can only see the other person's perspective, borrowing a pen and suddenly the person you borrowed it from wants $50 to replace a nib he claims you ruined - even though the FP novice could never get the damn thing to write!
Whenever I have the time to guide someone's use of a FP I find they often will have a few questions relating to ink and the nibs and where to buy them etc. I find this kind of interaction very rewarding and aim to always try to share the FP love!