Kindness in a grocery store

One time my mom was standing in the grocery store line. There was a man infront of her, and a woman at the register in front of him. The woman go out her wallet to pay for her few items, and realized she didn't have the money. She said.
"Oh dang it. I'm sorry, it seems i forgot my money at home. Oh, I guess I'll just come get this stuff later." My mom said seh seemed clearly upset, and was getting ready to leave empty handed, when the guy behind her said. "Don't worry about it, here, I have some money."
He started to get out his wallet to pay for her items. The woman was shocked and tried to stop him by saying things like "No, no you shouldn't do such a thing. Its not for you to pay for. Please, you don't need to. Its fine..."

But the man just handed the person working at the register the money and said "This is for this woman's food." And it was paid for.
The woman stared at the man for a minute, then asked "How can I repay you? I must. That was so nice of you to do that sir. Thank you. What can I get you?"
The man just looked at her, smiled, and said.
"Just do something nice for someone else."

My mom came home so excited and suprised by that. I'm glad she got to see it. Its nice to know that people still pull random acts of kindness. She said it was almost like hope.

Even those small things, can really make someone's day better :)