it's a bad idea to seek friendships based on similar interests and hobbies, because ultimately in the end they mostly end up spoiling them.. what was once your pleasing haven of marvels is now kinda "taken away" from you-- it's your most prized possession and your biggest pride, and it's as if strangers stepped into it and peeked at your secrets... in difficult times this makes you feel uneasy and you give them up, only to shelter yourself further more in these secret gardens of yours to "repair" them
You're weird. Sharing hobbies and interests with someone else can make the hobbies and interests more enjoyable and rewarding.
Why should hobbies be secretive, what don't you want people to take a peek at? 
arrr, not again... no one who really meets me views me as weird in the slightest... yeah it's my fault for always acting so zany on all these boards for so long, but it's solely because it's super-efficient to make people snap out of their pre-conceived ideas in topics
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what you say is right-- yes it really can enrich hobbies to share them with good people, however truly good friends are rare. what I meant to say instead is that one shouldn't _seek_ (!= have) friendships with the basis of looking for people with the same interests
what makes friends good friends is how compatible and naturally understanding, and drawn onto us they are, not how similar their likings are... and these persons are rare, most everyone doesn't really understand or genuinely appreciate us, we get tired and unsatisfied of our friends very quickly when they don't correspond to that ideal, they don't withstand practical life constraints... great friends are those who hold well beyond that
and there's no way to foretell who'll be truly great companions to us, it is purely luck, and very majorly people aren't compatible with one another... so it's still very important IMO to keep your most precious hobbies separated from your real life for such reasons, because as these're your biggest passions, in order not to soil them and to avoid being psychologically burned, they must be shared with the chosen few that you truly hold dear
