Seeing somebody with less should make you generous, not smug. Gratitude that looks down isn’t gratitude.

Comparison can produce two very different feelings and only one of them is worth anything. Noticing that somebody has less can make you aware of how much of your own situation was circumstance, which tends to open your hands. Or it can be used as reassurance that you are doing fine, which closes them. Same observation, opposite result.

Check which one is happening when the thought arrives. If it makes you want to give something or say something, follow it. If it mainly makes you feel better about yourself, that is the moment to stop and look again.