While by definition we work with computers/technology, I believe that we play our way to a solution. I often sit at my computer for hours at a time "working". This work is only defined as such because I get paid while doing it. I spend many hours of the day reading K5, /., freshmeat, and several other sites I may mention later; I know I am not the only one who does this. ;-) I am willing to admit that I do this on company time because my employer is already aware of it. My boss is acutely aware of something that most employers of geeks don't seem to know: we play, surf, waste time, and generally have the attention spans of small children and this is a Good Thing.
Working with technology, as many of us do, requires a lot of creativity to find innovative new ways to solve a problem. Our attitudes and work/play not only result from this excess creativity, they spring anew. If our actions seem, to the outside world, to be childish, then that makes sense; answer this: who has more creativity? A Microsoft programmer or a two-year old? The two-year old, obviously; why do think Microsoft uses them to design software? (Remember the commercials -- I'm not making this up)
Though our bosses may or may not understand this, the e-stores do. The average e-store knows that the majority of its business, especially its early business, is going to come from the people that spend the most time/money/trust online (namely: us), and they will try to temp us with goods only a geek would love. Shops such as ThinkGeek.com even specialize in the market. Someone who has never been to ThinkGeek may assume that it sells lots of gadgets, computer equipment, and other things we need to do our jobs/hobbies, and they do, but what the outsider doesn't know about is the Toys section. What logical use could an office have for a nerf gun?
If I still haven't convinced you, then why do we insist in spending so much time theming? This is certainly not an essential part of work. In the closed-source world, tools to theme are generally not available on OSes that are meant for business work, only for the home user who is just wasting cycles on the new version of Mech Warrior anyway. Speaking of video games, why do you suppose those were brought about? It wasn't always on the whim of corporate giants who wouldn't even know of the possibilities of gaming on a computer if not for early geeks. These are the guys who were playing games before any of our Operating Systems were invented (about 15 B.U. [before Unix]).
Within the community we spend many hours, not working, but talking on community sites. No other class of professionals that I can think of does anything like this. You never hear about how all of the accountants are hanging out in one place discussing the possibilities of a Accountants' Cabal. These other professions certainly don't spend as much time nor gather in as large groups as ours does. (How many K5 members and /. members?) Some may say that while we are gathering we are discussing work related issues. Are you? I rarely do; I discuss everything from algorithims for calculating pi to Linus's future with Transmeta if AMD buys them out.
It is while at play that I get anything done. If it weren't for toying with Perl and PHP (I just liked the names) then that important website would still be in development. If it were not for "playing" with Linux, as a hobby, I never would have suggested it for that project that was slated to use another OS. Not to mention we would be paying extra for someone to maintain our web server. I still want to play with MacOS X, developing a Palm application, wireless networking, and many other things; who knows what results it will lead to?