Two questions about etiquette:
1)Is it impolite to reply to "thank you" with "yup" to a casual stranger. For example, you hold the door open for them, they thank you, and you reply "yup" or something similar instead of you're welcome.
2)You and some acquaintances are going through a door (such as a store). One of them holds the door open for you, and tells you to go ahead, so you do, instead of insisting that they go first. I heard in middle eastern countries the host always goes last (for example you have company over, and they are entering your house. But what about a door that is not related to your house? Does going in last signify that you are more important/higher status (as if you were host)?
1)Is it impolite to reply to "thank you" with "yup" to a casual stranger. For example, you hold the door open for them, they thank you, and you reply "yup" or something similar instead of you're welcome.
2)You and some acquaintances are going through a door (such as a store). One of them holds the door open for you, and tells you to go ahead, so you do, instead of insisting that they go first. I heard in middle eastern countries the host always goes last (for example you have company over, and they are entering your house. But what about a door that is not related to your house? Does going in last signify that you are more important/higher status (as if you were host)?

