"Just so I'm understanding you clearly, you're saying that you'd sooner burn out your $300 WiiU overusing the DVD drive for games and movies, rather than buying a $20 DVD player? And once it's burnt out, you have no issues buying another $300 WiiU before you buy that $20 DVD player? And the reason for that is to save space on your A/V rack? Just making sure I read that correctly."
Absolutely. Take my bedroom setup for example. It use to be complicated with a DVD player, Xbox running XBMC, Gamecube, Dreamcast, a receiver, 5.1 speaker setup, on my old 27" CRT. Then my livingroom 360 red-ringed, causing me go grab a new 360 Arcade to replace it while out for repair. Once the repaired 360 came back, I decided to redo the bedroom setup. I gutted everything, put in a 32" Panasonic LCD, hooked up the 360 with a new HDD and called it good. The 360 mostly gets used for streaming Netflix and Hulu, plus a bit of gaming in that room for when the girl wants the big TV for whatever game she has gotten in to. It's played a DVD maybe a dozen times since it has lived in the bedroom. I would hate to have a separate DVD player in there to play a disc maybe 15 times over it's life, especially when the 360 sitting right next to it plays DVDs just fine.
My livingroom is a similar story, though it retained more complicated stuff. Instead of the ~15 devices that it used to run, I gutted it to contain my 50" plasma, receiver and 5.1 speakers, 360, Wii, and PS3. There is no separate Bluray player as the PS3 does that just fine after adding the Harmony adapter to it. I can play a DVD in either of the big consoles, which happens maybe once a month. Netflix and Hulu Plus on the 360 are better DVRs than any of my physical DVRs ever were. And with proper PC server software and sticking to some specific formats, the PS3 serves as a decent media streamer, mostly replacing my XBMC Xbox.
Of course, I run everything on Harmonys to simplify everything for my girl when she picks up a remote in either room.
So yes, I would absolutely replace any of my $150-$300 media devices with a second of the same thing if I broke it by playing too many discs, rather than add complication with a cheap $20 player. Hell, I couldn't wait the 13 days for my 360 to come back from service, before buying a new one on day two.

ADDITIONAL: To clarify, the issue is not rack space. The issue is simplicity.