It's a hard lesson to learn. I found that if I keep doing nice things for people for free, I get more requests again and again.

Soon I find myself doing everything for free, for a lot of people, and I run out of time to manage my own life.

Soon I have 10 people asking me to do free things, yet no one cares my wallet is empty, or that I have 100 things on my list that I need to do.

So then I mention I need help too. Want to watch 10 people turn around and speed walk away?

"Oh sorry @intelliguy, I'd help, but I can't because of this or that reason"

It gets funny.... if you finally observe what is happening.

I agree with you.. At some point, you shouldn't be giving what your good at away for free. Maybe sometimes, just not all the time.