I think it depends on the person. I have one brother who loves people and isn't shy by any standards, and loves to talk to people.
Other brother was more on the shy side, son slightly reserved but would and will talk to anyone who is polite. Daughter who is a guard in a Texas jail is chatty, but tends to be suspicious of overly friendly strangers.
Just be courteous and polite, cheerful, say what you have to say and then back off. If he/she is in a good mood (and you have no idea of what horrors they have seen recently) he/she will be glad to talk to you.