Link Hudson to answer your questions. In my personal opinion it is not a sin to have a hobby if that hobby is not destructive, i.e. fly fishing or tying flies, collecting stamps ect. Engaging in social activities with friends is a good thing, dancing, bowling, dinner, going on a picnic, having a get together for a BBQ, trail hiking, camping, taking a trip on a vacation, sightseeing, ect. As long as the activity is wholesome. Let your conscience be your guide. Or if you are a spiritual person, let the Holy Ghost becypur guide.