Trouble at work for helping another

So I work at a gas station and this guy came in with a sheriff and picked up a gas can and funnel and tried to get some gas but his card got declined so I paid it for him and then he came back and said he needed some more gas to make it home which was a good distance from my store so I bought him some more gas. I felt like I did the right thing but my gm came by in the morning and I pretty much got in trouble for helping someone in need. I think it’s kinda sad that a lot of companies discourage helping people but I can see how it was explained also I just feel bad that I think I did the right thing and I was in trouble for it.