Post proof of a subsidy! A loan paid back with interest is not a subsidy.
I fail to see how the 'profitability' of these special favors has any bearing. Unless you are positing profit as the point of government - which I would argue vehemently against.
We're really in the midst of a transition from a liberal democracy, based on universal rights and rule of law, to a corporatist state, based on group-rights and rule by decree. Under the 'new normal', your rights depend on who you are, who you know or what group you belong to. If your business, or a business you've invested in, is "too big to fail" or simply well-connected in DC, you're more likely to get bailouts and exemptions. If not, too bad. If you belong to a class or group with an aggressive lobbying presence, your needs will be attended to. If not, too bad.
Equal protection isn't such a bad thing. We should reconsider it before leaping to the bottom of this ravine.