Recently, I was lucky enough to be given the opportunity to photograph a mate's wedding.
Lucky? Yeah, because he and his wife had hired a professional photographer to ensure that all the bases were covered. And with the Cold War style proliferation of digital cameras amongst wedding guests these days, I could pretty much focus on... well, whatever I wanted, and still got to enjoy the wedding as a guest!
I didn't have to worry about making sure I got a photo of the bride's family or even if my shots were in focus; one of my favourite photos from the wedding is the blurry little guy on the dancefloor.
If I was doing it as a job, I wouldn't have had that luxury. You have to make sure you get the key shots, and once you have all of them, you might have some time to do some experiments ala Ryan Brenizer, if you're lucky... (I'm not saying professional photographers can't enjoy their work, just that its not always fun)
Similarly, I went on a road-trip from Sydney to Brisbane over the Christmas/New Year's break, and of course the camera came along... but I made sure to take plenty of shots for me that (chances are) nobody else will like. Like an old Nissan Urvan on a beach at sunset.
And no, its not a great shot, the sunset is hugely overexposed so I can show the detail in the van, because the derelict van on the beach is what appealed to me.
A hobby should provide enjoyment, remember to enjoy your photography.