I have a friend that chose general practice in the mountains earlier in his career (Later switched to EM). Depending on the ability of his patients to pay, he would often barter. He told me that he would often peek out the window to see what kind of car they were driving, the number of kids riding along, and whether or not they were wearing good clothes/shoes/etc. If he felt they were really poor he would suggest an easier alternative to payment (usually based on the profession/hobbies of the parents). He would casually remark "I sure could use some firewood...do you know who I could contact to find some?" or "I sure would love to go hunting one day, I haven't been in years." Usually they would reply with "I just happen to cut firewood" or "I hunt all the time." Of course, the truth is that he usually did not need the firewood, and although he did enjoy the hunting trips occasionally, he primarily did it to preserve the dignity of some of his patients when they could not afford to pay.
So, while he does not do it any longer (that I am aware of), 15 years ago he did...