Swenny, you've posted a cogent, self-aware analysis of your thoughts on farm renting practices...that alone makes it worth reading.  There are many ways that a farmer can expand his land base, one of which is to cash rent.  Here's my position on ethics in agriculture, and the nature of cash renting.

Quite simply, a rented piece of ground is worth what the tenant and landowner agree it is worth.  That sounds trite, but it is the fundamental tenet of economics.  Something is worth exactly what it moves for.  The farmers who aggressively cash rent ground understand this, and they structure their whole farm to balance out across their acres.  They tend to lease more equipment, rather than own the paint (to increase liquidity) and they tend to be outstanding grain marketers who pay only what the market will bear.  If they know that the current price of grain will support a given rent, then they will likely sell an allocated portion of grain at that field's known APH to set a floor and protect their riskier investment.  That is smart business.

Which leads me to...the ethics of cash rent.  Ground is the be-all, end-all of non-fungible farm needs.  If you want to be competitive in a day and age where ADM and Cargill are quietly building a land base by locking in producers with grain bin and input-support programs, or buying farm management firms, then you'd best do everything you can to fight back.  That is the point that many producers fail to see - your enemy is not ILLFF or the latest operator profiled in Top Producer.  At the end of the day, your greatest challenge will come when the grain processors and end users begin to seize control of acres.  Oh, they'll let you farm it by paying just a little more than you might make on your own, but you still belong to them.  There's nothing ethical about that, but they're doing it anyway.  Why?  Because business is AMORAL.  It is not IMMORAL or MORAL; it exists in a universe of stone-cold self-interest.  ILLFF appears to understand this concept, and is weathering the slings and arrows in order to ensure survival. 

The farming lifestyle has a beautiful tradition of proud self-reliance and a "by the bootstraps" mentality.  Traditionally, a man's pride was in laboring to produce a healthy herd of livestock and good corn.  Those days are mostly gone, and with them the ability to remain completely independent.  It seems to me that the wise thing to do is to find an opportunity and a method of growth that works for you, and do it.  ILLFF is cash renting ground according to a pay structure that works for them, and is pretty much the most-hated outfit on NAT for it.  But, they'll probably be surviving and prospering in a near-future that will find most producers scratching their heads and being faced with the decision to either (1) sell to ADM/Cargill/Bunge, (2) find some group of farmers they might actually agree with to increase economies of scale, or (3) retire and sell the iron.  In that scenario, the only ethical thing to do is what you feel is right.