On one hand, I feel like political donations should be open and available. Seeing what candidates draw their support from who (and in what amounts) does seem like a measure that acts against corruption by exposing that entire field to the light of day, and it is a field where the US has had some dramatically negative history and consequences before attempts were made to combat things (the Montana 'copper kings', or Carnegie steel and Trusts in general as dramatic examples).
On the other hand, there is point to be made that such support should be anonymous information for much the same reason as voting choices themselves are anonymous. Even ignoring that, it's clearly counter to the spirit and purpose of these laws to use donation lists by small individuals as something to target boycotts or ostracization by their city and neighbors. Castro's act very much was a case of 'punching down', to use the colloquial, and the purpose of these laws should be to cast a light on major donors and organizations who could or do conceivably buy influence--not every Tom, Dick or Harry who threw whatever amount of dollars to a political campaign that spent hundreds of millions of dollars. There's a question of proportionality at the very least. PACs and superPACs would be MUCH better targets for Castro's ire in this regard since, as I understand it, their oversight is looser to begin with (and they don't have limits so there's more opportunity for back-scratching, favor-making deals!),