I think myself and a few other programs I know of with higher minimums that are NOT scams should be rather insulted by this!
I personally own a program that has a $100 minimum, and I lowered it from my original, it was originally $150!
Yes, a higher payout program does take a lot longer to earn the minimum payout in. And in many cases a member will indeed get disgruntled and leave which does indeed help site debt, but that isn't what some POs were thinking when they set a high payout.
Some might have been thinking, hey, if I have a higher payout, I won't get flooded with requests all the time and can pay my members within days of request, instead of making them wait forever.
Or they could have been thinking that by doing that, they could encourage more members to invest in upgrades that include lower payouts and advertising, which helps keep ads flowing

(and also gets the member free referrals and gets them to payout that much quicker!)
Or who knows what else in the case of those that are not scams. But I can say, there are some great programs out there with $100+ minimum payouts. To name a few: MikesPaid4Email, ProPaidEmail, TheCashDoctor, NoFlashJustCash.
And I also know when I get payout in those programs I am still a member of, I will be very happy to see my $100+ in my paypal for my work. In the long run, I am going to earn more with some of these programs than I would with some of the programs with smaller payouts

(and of course, there are some exceptions). And this is even with my wee little downlines of 5-20 people

All I know is that I am getting sick and tired of having to defend myself because people assume that high payout minimum=scam