It’s easy to be charitable to people who are polite, grateful, etc., but it can be harder to extend that same charitable nature to someone who makes you feel uncomfortable or doesn’t seem grateful. However that should not be an excuse, community service is not a tool to make one feel good or increase one’s social standing. In order to be truly charitable you need to put yourself in their shoes and do your best to understand where they’re coming from. Sometimes that can be challenging, but even if you cannot understand the motive for their actions that doesn’t make them less deserving.
I’ve volunteered at many different locations (animal shelters, nursing homes, etc.) and the most challenging has been my work with the disabled, especially with nonverbal children. It can be very hard to understand what they want/need, but that does not mean I should show my frustration. I’m the one with the responsibility to help them and they’re not obligated to make my job easier.