I already answered your first point. By supporting a kollel man learn Torah you ARE helping to heal the sick, feed the poor, etc. The Torah is the source of all brachos and the more that is learned the more bracha comes to the world. As we say in davening “Talmidei Chachamim marbim Shalo-m ba’olam…al tikra banayich ela bonayich”.
This has nothing to do with meisras nefesh, although that is not to say that a kollel man doesn’t have that as well. If you would like to know what kollel men give up I invite you to come to E”Y. See them with wrinkled suits because they can’t afford the cleaners. Come see their cramped apartments. See what their meals consists of every single day. Hear them asking to be paid back the one or two shekels that are borrowed because they can barely afford to give even that up. Feel the cold apartments of those that can’t afford heat and instead need to bundle up their families.
What are your work hours? How many days a week? Do you work from 9am until 7 pm on a daily basis 5 days a week. Do you put in additional hours on Friday, erev Shabbos or maybe on Shabbos itself, to get a few extra dollars? Do you have a ‘night job as well’ from 8-10 to get some extra groceries? I have a friend who is out at 5am and doesn’t get back until 10:30pm every day of the week. What exactly do you mean ‘no mesirus nefesh’?
Rav Shach says that kollel men get their parnassah outside the derech hateva (Rav Shach Speaks). When kollelim come to you collecting money, you are not doing them a favor. They have the bitachon, they will get what they need somehow or another. Hashem already designated a certain amount of money for each kollel. If you don’t give it someone else will. They are doing you a favor by giving you a zchus to be a part of the mitzvah that is kneged kulam.