rent-a-cow attrib. indicating a situation in which livestock are deceitfully used to make a residential or commercial property qualify as a working farm or ranch in order to benefit from an agricultural tax provision or subsidy. Editorial Note: There are literal rent-a-cow operations, from which one can lease cattle for a variety of legitimate purposes, but the use here is largely figurative. (source: Double-Tongued Dictionary)
Further reading
To describe something tiny or insignificant compared with something vast, you might reach for phrases like a drop in the ocean or a drop in the bucket. In Mandarin, there’s an equally picturesque phrase that translates as nine cows, one hair, 九 牛 一...
Secret signals on the job: Waitresses at some 19th-century restaurants ensured speedy drink service by communicating with a non-verbal code. One server took orders, then placed each customer’s cup to indicate exactly what the customer wanted...
Would it be possible to modify the word “deceitfully”? Your examples do not provide cases of deception, but merely people who read the laws and implemented procedures to comply with them and recieve tax breaks. While the authors of the law may not have intended it apply to Fidelity Investments Texas campus, Fidelity is not trying to decieve people into believing it is cattle ranch and not a financial services firm. There is a significance differnce between saying “this is a working farm” and “the lower corner is mowed for hay to qualify for the Ag tax rate”, in the former there is an attempt to decieve in the latter there is no such attempt.