What is value of pursuing a vocation, hobby or activity that you love?

It would seem that this is a two part question with vocation being in a category itself. I liked teaching. I could not picture myself doing anything else. I liked the kids and the people I taught with. I liked seeing my students get turned on to science or really improve grade-wise when they put forth the effort. I was not like some educators who hated to see summer vacation come. They could hardly wait to get back to school in the fall. Not me. I enjoyed summer activities and the freedom too much. However,rarely was I in a hurry for summer vacation to come or the end of my career. I was content at what I was doing. The value of what I did? Theoretically to expand the students knowledge and appreciation of the world around them. Many times I would have a student tell me that they never really liked science until they had my class. You really never know what is going to interest you until you are exposed to it.
A hobby is entirely something else. The reason you do it is because you love it. If I might return to the last statement of first paragraph. One of my hobbies is bird watching. I never would have developed that interest if I had not taken an Ornithology course for my last bio elective before graduating. Up to that point, I had no interest in birds at all. Birdwatching was for twits! I had a most enthusiastic prof whose energy was inoculated into me. I became aware of the special creation of God called birds. Their whole adaptation to flight was incredible. To this day, I enjoy watching and identifying them. Value? A chance to see evidence of the Creator and the vast variety of what he made.
I love to bicycle. I remember the first year after I had bought my first good bike, I was about 5 miles out of Amery. I was thinking that all I had to get me back to town was this contraption made of two triangles, wheels, assorted parts and my body. I remember thinking that was pretty cool. I felt powerful, sort of. One can travel all over with a bicycle. What a great way to see anything; nature, old towns, even people. Value? You are taking care of the one body you have to carry yourself around in. If you are in the city, it is a money saving device, right, Don, Katie, Matt?
Photography has been an interest of mine for about as long as I can remember. The Famous Photographers School that I took a correspondence class in when I was in the USCG was a great help to me. I had my own darkroom and developed my own BW film and printed my own enlargements. I learned about filters, lenses and composition. I bought my first nice camera, lenses, flash etc. during my enlistment. Combining two of my passions, I have enjoyed taking pictures of birds. I also love taking pictures of God's handiwork that surrounds us. Value? Being a pest to my children at times when the old man is trying to get a pix of everyone. Seriously, since I have no artistic ability, it pleases me to take a well composed, exposed picture of nature. I can't improve on what He has done but I can record it for future enjoyment.
Don't know if this would qualify as a hobby, but I love to spend time with my bride. Being my best friend, and one who sort of understands me, it is most enjoyable to be with her. Value? Sure makes life a whole lot better, don't cha think?