I know this sounds nasty, but I have been forced to take a different position about the collectors in shul. Assuming they already davened, I was not there to disturb them during davening. I believe I am justified to claim the same courtesy.
Today, the desperation for funds is so great that some of these collectors are willing to violate the basics, by insisting on collecting during parts of davening where one may not be mafsik, by insisting that one give more than they wanted to give, and by shortchanging (“I only give $18 change for a 20, because it equals chai”). Some fail to get permission from the Rov or gabbai to speak after chazoras hashatz to make their “sales pitch”.
One can certainly continue to give tzedokoh at the same levels as before without rewarding these collectors who are bothersome. I say this fully aware that HKB”H sends these opportunities to us to test us. HKB”H deals with us midah kineged midah, and gives us in a manner similar to how we give others. I do feel bad for those who are stuck stooping to collect donations from others. I do not envy anyone in fund raising, nor do I have opinions how to do it successfully. I do know what offends me.
Some time ago, I offered $1 to one of these collectors who insisted on a much larger donation, which I simply could not afford. He handed me back the $1, and refused my efforts to give it to him again. I allowed him to see that I was placing it in one of the pushkas in shul, since I had already designated it for tzedokoh. I feel for him, but that does not place money in my possession to be available for tzedokoh.
I mourn the loss of chashivus of this precious mitzvah.