Alcohol is acidic and it is absorbic (acts as a desiccant pulling moisture out of the air). So anything that is going to be affected by a strong polar compound or acidity will have problems (such as paper fuel filters). This includes natural gum rubber used as a seal in a lot of places, or as a lining of old fuel lines.
President Jimmy Carter (remember him?), that’s how long ago this has been in effect. What you say? A presidential order stating that all cars manufactured after 1973 (which includes the tuned port injection system off of the Camaro's 305 motor) where to be made capable to use alcohol instead of gasoline. This was because we were going to stop buying gasoline from our friends the Arabs (and Persians) in the middle east and grow our own fuel supply.
Well as with any bureaucracy it took a little longer to implement the presidents decree (from 1980) and enact it into law. But it finally happed in 2003 when congress mandated by law that all fuel sold in the country should have at least 10% by volume alcohol (the goal is 85% according to the law but don't hold your breath as the gas companies are fighting the conversion tooth and nail the only way they know how by buying congressmen and senators to vote foe them and not their constituents). All cars should work fine with gasohol and I do not believe the injectors where the problem with your friends car (they are made by Bosch and the Germans have used gasohol for decades).
What probably happened is the duty cycle to supply the engine caused them to burn out. When running gasohol you have to burn more of it to get the same mix of fuel to air that you do with gasoline (stoichiometric) Add to this an engine requiring more fuel than a stock 305 would want to deliver normally and you exceed the 75% duty rating of the injectors (you are supposed to use a bigger injector rated in pounds of fuel per hour when using a 305 manifold on a 350, or even a 327 if your going to be revving it up).