I'm surprised "having a bonfire" isn't on this list, but I'm afraid to see how detrimental it might be.

The nostalgia factor is sort of wearing off now that I'm 40 and don't want my clothes to smell bad or have a low-key asthma attack. The last time I went camping in a campground and everyone had a fire going, the whole park was completely choked with smoke that it made going for a walk really crappy. It's such a weird activity, driving cars out to the woods to pay to burn dead trees.