If someone asks, I'll offer to buy them food or other supplies. My wife hands out handwarmers during the winter. We used to put together care packages for people, but lost the habit. I don't give out money because I don't want to enable addictions. When you offer something other than money, you are able to more easily separate people who want a fix over people who want to improve their situation. Your resources go farther when you help the latter.
edit: One thing that helps people out a lot is buying them public transit passes. It gives them mobility to get to shelter/services they wouldn't have access to otherwise.
Cleaning also takes less time, especially if you include all the planning that goes into cooking. Then if you consider the amount of time it'd take for the same meal to be made by other members of the household, you start to see that cleaning is actually a bargain. You also have to remember that even when you enjoy cooking, it is stil exhausting. They have less energy to clean than those who didn't cook.
Obviously there is a limit. If the cook is making an excessive mess due to doing some particularly fancy cooking out of ambition, they should probably help out. But if you regularly reap the benefits of someone else's skill in the kitchen, yes, you should help clean.