Let me enter your world - but stay out of mine

Last night an odd thing occurred to me.
Yesterday afternoon, Laurie and I joined several friends from Encounter in downtown Dallas at the Austin Street Shelter.
We went and brought crackers and some small gifts like socks and toothbrushes, etc.
It was great to have an opportunity to serve and share with the men and women waiting outside the homeless shelter.
I had no problem talking with the men and women outside the shelter. I had a good time talking with Wayne, Frank and Steve (I hope my memory is right there). I also had no problem talking with people on the streets in Nigeria.
But then last night, Laurie and I went to a Missions Banquet at our parent's church.
Having just come back from Nigeria for two weeks, I have a new found respect for missions and the sacrifices they make.
We had a good time and afterwards we went to the store to pick up a few items.
When we went to check out we noticed the one cashier at his register was standing there with the light to his lane out.
We weren't sure if it was open or closed.
The cashier went on and on and on talking about how the light switch was missing.
It annoyed me. I wanted to pay for our groceries and leave and not be bothered by someone chatting about a missing light switch.
I didn't care.
I was in my world, my element and didn't want to be bothered.
But as I walked out of the store I thought, "Why is it that I can talk to someone at length on the streets of downtown Dallas or Jos, Nigeria, but if a cashier at Kroger's wants to talk to me I get annoyed? Why is it that I can barge into someone else's world and talk freely, but if they try to interrupt what's going on in my world I get annoyed or frustrated?"
I pray that God continues to give me a heart for His people - whether that's in Jos, Nigeria, downtown Dallas or at a Kroger's in Garland, Texas.
Anyone else ever feel the same way?