Only $100,000 per-month is less than 20 to 30 peoples wages per-month. Got more than people to pay than you're bringing in? Then they're losing month every month.
That's just simple maths, everyone complains about it being a profit driven and greedy industry but if you can't pay people then the company goes bust... then everyone complains about how they were too stupid to manage their finances.
The Wii-U is also quite weak, quirky hardware, extra tablet interface that demands more development and possibly gameplay changes to use well. That takes more peoples time and thus costs more money. It means that you have to spend more to develop your title for it so you've now got three choices:
1: You release on multiple platforms but spend a bit extra on doing some extra feature for Wii-U?
2: You release on Wii-U only, designing for the tablet and other changes, really push that angle and hope that there's enough of them to recoup the cost (which aren't appreciably lower despite only being for 1 console)?
3: Ignore the Wii-U and sell on the Xbox360 & PS3 which already have huge installed player base, you already have the tech' for and you know you don't have to make any effort to change the controls etc.
Everyone's choosing #3 because choosing #2 would be financial suicide, and now they're ditching option #1 too because there's just not enough of them being sold to make it financially viable.