They do see that it does that, and they incorporate the guilt into their collecting. Why else would they go to the trouble of walking around dark cold streets in the evenings when people are at home eating or sitting beside their fires? It is much easier to go en masse to a shopping mall or busy street, stand in likely places and holdout your can to the hundreds of people passing by.
If you confront people on their own doorstep, they give more. Why? Because they are a captive audience, who can't pretend that they have not seen you, and they are embarrassed to turn you away empty-handed.
So they are being shamed into giving and feel resentful. If all you want is one donation, for one charity, this one time, you have gained. If you want goodwill, and a donation for the next good cause, and for your own charity the next time, you will have to try harder the next time, and the next person calling (probably just a week later) will get the earful you have sown.