Even though it's been a very long time, I feel I should respond to drystyx:
These were not "big stars". They were well-known and respected character actors at best. George Kennedy had very recently made his debut and was yet to become famous with Cool Hand Luke, so he was basically an unknown. Ian Bannen may have been big in Britain, but he sure wasn't in the US. Dan Dureya was very famous, but past his prime and also a character actor whose only starring roles were in B movies mostly from the late 40's and early 50's. Peter Finch certainly was a big deal at the time, but not a huge Hollywood star. There's no doubt that the frequently typecast Borgnine and Kruger were also character actors. The only real big time Hollywood star in the movie was Stewart and he was certainly past his prime by that point.
What I'm basically saying is that the cast was indeed impressive at the time, but not as star-studded as it may seem in hindsight.
I'm here, Mr. Man, I cannot tell no lie and I'll be right here till the day I die

Duryea was outstanding as Stewart's amoral, tough-guy adversary in "Winchester '73". One of the best heavies ever in that one.

he was a close friend of james stewart and worked with him several times.

Yes, a departure for one of my favorites. One thing about the film that certainly was not lost on the movie viewers of 1965, was that many of these were pretty big stars at the time-George Kennedy, Dan Duryea, Ernest Borgnine, and Ian Bannen, yet all were barely more in cameo roles here. I think it was to bring out audience expectations to see them do something rash or active during the film's first viewing, only to show that they were tired men in a rash. I think that's the reasoning for having such big names in roles that were so quiet.
Now go away or I shall taunt you a second time

I've been watching him for well over forty years and I don't think I can recall a performance by Dan Duryea that I've ever been disappointed in. Watch him as ' Duke Pastrami ' in ' Ball of Fire '.

Yes, this was a tour-de-force ensemble and he was an important part of it.
For who would bear the whips and scorns of Hollywood (;-p)