I agree with you that it is plausible that such a plan as you describe will have some degree of success.
For one I think it makes for a really great plot, both for a covenant in a "trial" area where the redcaps a trying it out and from the perspective of a group of Merceres trying to pull it off.
Imagine playing in a tribunal that has been singled out as a test area for the plan. Either you accept and ta-da your economic problems are gone but now you are reliant on house Mercere for support and you will have problems opposing them at tribunal and you will be in their debt, even if it is purely a debt of gratitude.
If you dont accept you have to try to make do while all of your neighbors get a huge leg up from the economic headroom available to them because of the extra money and goods they have.
Once the players figure out what is going on they can either accept their fate and try to negotiate the best deal for themselves that they can or they can try to face off against the conspiracy on the political arena. Lots of great opportunities for drama and conflict.
The good thing about running it as a saga is that it doesnt matter whether or not this is a thing that is plausible to succeed in the core setting proposed by Atlas games nor whether it happening is a social and economic inevitability. What matters is whether or not it would make for a great story, and IMO this certainly would.
In criticizing your method of asking I am not trying to say that it is a stupid method and that you are bad for doing what you did. Professionally I am an academic and I have some exposure to the problems that come with questionnaires and that is what I am trying to get at. Obviously you are not trying to adhere to academic standards for asking questions and shouldnt be, but you still face the same problems.
For one the question you pose is sufficiently generally worded that it is, IMO possible for two people to read the answers given to the questionnaire and reach different conclusions. Which is bad because it makes it hard to have a reasonable discussion about what the answers mean. A generally worded question also leaves a lot of room for interpretation up to the answerer.
There is evidence for divergent answers in the top of the thread, where one person (Bitter) answers that they want to take the money to see what the consequences will be. (which is an out-of-character answer) and lots of examples of people answering from the perspective of their characters. This is even where you stepped in to clarify.
Another problem is that we all have wildly different underlying assumptions that we answer out of. We mostly dont bother stating those assumptions. For example I assume that even if the gift is given in kind it will still result in an increased cash-flow for a covenant. I assume this because I also assume that most covenants are reasonably well diversified in their economies and that even if they lose one source of income they will still have other sources that can given them cash. Anyone might reasonably disagree with my assumption. I also assume that it will be clear to most magi that there is no such thing as a free lunch and that they will naturally be suspicious of the offer and proud (or prudent) enough to try to use the gift to build up their economies instead of relying overmuch on it. Again it is reasonable to disagree here.
The point I am trying to make is that our underlying assumptions change how we answer and how we interpret the results of the poll. The OP did not to a sufficient degree specify which underlying assumptions we should use that we are not having this discussion now. (Again I should specify that I dont think that it is a failure on your part that the underlying assumptions were not specified, since it is highly unusual to state such assumptions, and it is generally also difficult to figure out ones own assumptions.)