Donations, especially large donations from larger corporations are often given not out of the ideals of charity or good will, but as a public relations campaign designed to make people forget the sometimes bad things that companies do. For example, oil companies will donate large amounts of money to green sounding organization while pillaging the environment.
Donations can indeed mask responsibility, but doing so is up to the discretion of the donater. Say one donates to a homeless man. You are either helping along in staying homeless and without responsibility, or you are helping him find a job adn stable income. It is up to the donor to decide whether or not he is helping.
Giving a donation may seem like a lazier option than going out and volunteering to do some sort of proactive mediation, but when you look at it closely, it really is not. The person making the donation worked hard for that money and now he/she is doing a good thing and using it to make their community a better place. We all do have a responsibility for our fellow human beings and donating money is one of the best ways to help out those who need it.
I do not think that the sole act of donating is always a means for a person to make responsibility. I do understand why some might think so. There are some individuals who donate to bypass having to take any type of proactive course for a cause they believe in. But not everybody has this mindset.
I think that when someone makes a donation, he or she is just trying to help out the people that need some assistance, and are not trying to hide the responsibility that they might have over a topic. I think they are just trying to look good and help out.