how can it be that all movies are available at walmart online? are apples conditions worse for the studios?
Yes, although some might disagree.
Walmart has handed the keys to the studio and let the studio dictate all terms (pricing, distribution, and title availability).
On the down side, Walmart is clearly in this as a spoiler, not as a true market competitor, aiming instead to keep their in-store DVD empire vital instead of fostering a whole new market. Thus, you see that prices are essentially equal to the real, tangible DVD prices (not sure if WalMart or the studio gets the extra profit from not having to manufacture and distribute physical media). Thus, you see that many/most titles you search for lead you to a link to order the DVD only, not a download link.
Some (many) might argue that signing with Walmart in this manner is, long term, quite detrimental to the studios. Then again, both the record and motion picture industries have been known to favor short-term profit or even stagnation over investing for long-term success.
if itunes want's to stay in the video market then they better convince the studios and get all movies online. maybe the studios fear itunes success and down the road monopol but they have to convince them.
because all people who set up their computers/media centers for the walmart store are lost customers for apple/itunes. and no, i don't think that the fact that walmart movies don't play on ipods is going to save itunes. i don't see a lot of people watching $10 movies on a mini screen. $2 tv shows yes but not movies.
I don't think the iPod will drive iTumes movie sales either.

TV, quite possibly. People want to watch movies in their home theater setup, period.
Fundamentally, though, I'm not so hot on Apple's current movie offerings either. They still cost too much (even if $9.99 were an across-the-board price) for what you get (down-resolution, compressed video; stereo sound instead of 5.1 or greater; no extras; no dvd insert even) and are too difficult to pipe to the living room (having to spend multiple hundreds of dollars for a new set top box with only this functionality doesn't seem like it will take off). Spicing up the

TV might help in the latter regard, but I think really we'll need another round of industry concessions before downloads really become mainstream. And we have barely even started this first round!