If a friend or family member is passionate an activity, then I have a policy of not buying gifts aimed at that particular passion. My thinking is that (a) I will never know enough to make a good decision for a person and (b) if they don't already own that item, then there must be a reason. Instead, I try to buy things that fit with a new area of interest in that person's life or something I know that they used to enjoy, but don't focus on doing enough anymore.
If you're determined to get something in the general "passion zone", then you can always get something that supports or reminds the person of that passion. I'd rather get a coffee mug that says: "I'd rather be camping" (with a national parks pass tucked inside) than a new tent I don't want or need. That's my line of thinking anyway.