My lab and my hosting setup are actually fully segregated, but as far as why I'll go the more complex route I'd say its simple:

• I have the hardware (I get things through my work, sometimes to test for clients, etc)
• I have the knowledge
• I can give my family a better experience than the big companies offer
• Because I like to keep my skills current
• Some of the time, manufacturers send me things to test out or develop features for. After passing the lab testing, if I like it I'll add it to my home and maybe make some more fun things happen.

So the short version is just "because I can". I don't stress over outages or anything, if I'm out then I'm out. I UPS with NUTs because I can, and because that data is also useful for me for my work.

That same approach applies to other aspects as well. If I'm not interested in doing something, I just don't and I move on.