"I think it is a smart business decision from developers/publishers to stop supporting the Wii with those types of games, because if they do not get a return on their investment, why should they care? To please fanboys? "

Not selling well is NOT the same as not getting a return on an investment, especially with the budgets of those games lower than HD games.

Plus since most of those games made money, it shows that more of those games can, you know, still make money.

So claiming it only pleases fanboys is just a fallacy.

I think No More Heroes and Prince of Persia are two of the better examples.  That should have sold pretty well.  However, I think Madworld got "okay" reviews.  With Red Steel 2, people associate the name with shitty games because of the first one.  And the Conduit is just a "meh" fps.  And the Resident Evil games...ports. 

While I do think the consumer base is partially responsible for third party shying away (not every game Wii players got are bad), the same effort wasn't made on each console I think.  It's very interesting, worst support of any market leader ever I believe.

I haven't seen that many ps2 ports on 360 either...

That has nothing to do with the OP. If you read it, you would know why.

"While I do think the consumer base is partially responsible for third party shying away (not every game Wii players got are bad)"

That would only be valid if good games never had weak sales on other systems, and that is not the case on any system.

The No More Heroes games are good but they are also very niche games. We're talking about an ultra-violent, pervy, otaku main character in a highly stylized hack n' slash game here. To get big sales you need either well known IPs or something with mass appeal. The successful games on Nintendo consoles tend to lean towards the more creative/unqiue ones that channel values similar to those in Nintendo 1st party games. Instead of Prince of Persia, which is considered an older series, why doesn't Ubisoft make an Assassin's Creed title for Wii? Almost none of the big 3rd party developers are putting their best teams on Wii games and it really does show. It's a Catch-22 situation here. 3rd party games haven't sold well on Wii so they don't give Wii projects big budgets and marketing. Without big budgets and good marketing 3rd party Wii games probably won't sell well.

Prince of Persia Rival Swords for wii sold almost as good as Prince of Persia Forgoten sands for 360. Just 0.01 million less.

Red Steel 2 sold poorly but the original sold 1.20 million.

World at War for wii, a port that supported less multiplayer players then the HD versions, had virtually no local multiplayer AND had worse graphics sold 1.58. That's twice what Alan Wake did. Resident Evil 4 sold 1.79. It was a port of a gamecube/ps2 game with worse controls Both of these outsold  the 360 versions of Battlefield: Bad Company (1.38) Prototype (1.18) Dead Space (1.05) Splinter Cell: Conviction (1.47) Arkham Asylum (1.57) and Final Fantasy XIII (1.56). The only problem is thir parties often spend more on single HD games then they have on all their wii games over the past 5 year (Capcom, Sega and Junction Point Studios excluded)

EDIT:

Monster Hunter Tri 1.62
Umbrella Chronicles 1.42
Lego Batman 1.75
Sonic Unleashed 1.52 (Far better then both HD versions put together despite being a worse game)
Force Unleashed 1.49
Call of Duty 3 1.46 (A port of a last gen game. Outsold the original release and the PS3 version)

And, just for fun
Okami 0.30 possibly undertracked
Okami for ps2 0.15

ANOTHER EDIT:

And all those multiplatform titles which don't sell on wii (Care to mention one that isn't prince of persia) don't sell because people don't want to play watered down ports.

ANOTHER ANOTHER EDIT:

OWNED!!!

"Resident Evil 4 sold 1.79. It was a port of a gamecube/ps2 game with worse controls"

If you mean the Wii version had worse controls, I will have to virtually smack you.

Yes, Wii owners care about online, just look at the sales of Mario Kart and the Call of Duty games. Heck, the Conduit would have sold more if it did not suffer from online problems. Yes, Wii owners do care about online and that's why NBA Jam will not sell  as well as it could have.

Um, Mario Kart aslo has local, and CoD sold far less than the HD versions that have local.

So those are not good pieces of evidence that Wii owners care about online to the point of not buying games without it.

Plus NBA Jam has almost no marketing, so you can't just assume lack of online is affecting sales when that factor has to be taken into account.

Mario Kart also has online as well. We can not just ignore that fact. Call of Duty games are advertised for the HD consoles, have download content, and voice chat. The Wii games do not have advertising, No download content, and do not feature voice chat. Furthermore, Call of Duty 4 skipped the Wii and that affected the Call of Duty fanbase on the Wii. The port came two years later and still sold over a million copies. My evidence still stands. Wii owners do care about online.