Why is my husband being so rude to my family?

I have been married for over 4 years. I have 2 sisters who live near me. My sister's car can only be driven to work and not long distance right now. I took my sister to have her federal taxes done today. It turned out that it will take a few days to get her money. My sisters money was completely depleted because of rent and bills. My sister promised to repay me when she gets her money. She only borrowed around $40 for food. I picked up my husband from work. I was completely exhausted. I asked him to come with me and drive them home. He never talked to them, was rude and cold to me even. We stopped for gas at a corner station. The station is almost right across the street from our apartment building. Instead of driving them home, he decided to walk home. My sisters were insulted. My one sister has agoraphobia. My other sister is her caretaker. She is a nursing istant and works full time. She pays all her bills by herself and has only a little bit of money left after paying bills. I couldn't let my family go hungry. I find myself torn between my husband and my sisters. My sisters and I lived together after our mother died of cancer for economic reasons. My normal sister works hard for everything she owns. Shouldn't my husband apologize to my family? His family is not at all close. The only call around holidays. They never keep in contact. Is this the reason he doesn't understand a close knit family? I'm trying to understand him. Thanks.