When Gen Z doesn't use words is it a disrespect?

I notice a lot of times when I'm out at stores and interact with Gen Zs they will try hard as possible not to speak to me. Yesterday I asked a guy working at Walmart something about the phones without contracts and he didn't say anything just pointed at a sign. A lot of times I'll be picking stuff up at stores and give them the name of my order and they will just give it to me and walk away without any words said. I will add this is mostly African American or Hispanics also so not sure if it applies to White Gen Z. Thanks.