My semi-educated guess is that they are betting that most players on the $5 plus ($25 per game) VP machines really don't have the bankroll (see sorokin and kelly formulas) for that level. Advantage players do, but they are probably in the minority (not many people can easily handle a $20 plus K loss). I am certainly one of the under bankrolled when I play the *&^(?!! NSUD $1 - 10 play ($50 per game) or 3/5 play (at least $15) multilines in New Awleans. $1K does not last very long on those machines. I then quickly retreat to the $1 JOBs. 
Also, I think that their actual $ hold is better on the $5 vs $.25 although the percentage may be the same even when you consider the advantage people.
Bob
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--- On Fri, 11/6/09, rreid0859 <rreid0859@yahoo.com> wrote:
This is a question that has always puzzled me. I see casinos, Harrah's in particular, remove attractive but losing paytables (9/6 JOB, NSUD etc.) from all but the highest denominations ($5, $10, $25). I read that well known advantage players are working these plays. I assume they are playing at advantage when cash back and bounce back are taken into account or they would not be playing them.
Why would those casinos offer advantage plays at large denominations but not at quarter or dollar denoms where the risk of offering them is less? Are these casinos betting on the premise that those players really are not sufficiently bankrolled for >the plays?
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