On the flip side the "marketing" scheme used, many of these donations may be coming from people who in the past never gave anything to charities. That's the part we really don't know.
I suspect those giving to the ALSA fall into one of two categories:
1- those that are already regularly charitable and this is in addition to their normal giving.
2- those who rarely or never donate to charities.
The fact is, for many folks, this is a moment they take out of their lives in order to help others. I'm not going to be cynical about it, but rather celebrate it while accepting that many will go back to not giving to charities as soon as this dies down. But some will want to continue helping and will find their own charity to support...
It just seems odd to see (a very small percentage of) folks complaining about people being generous.