ANSWER:

Chili and lemon are things people eat and must be respected and not stepped on as any other food thrown on the ground. 

Avoid stepping on it not because it would harm us rather because it is an edible thing. 

QUESTION: In my country there are chilli and lemon out there randomly on the road put together with a thread.People in my family say that prevent stepping on it as it might lead to black magic on you.Is it shirk and if I encounter something like this what should I do ? Is this a minor or a major shirk ?