أَنْتَ أَحَقُّ بِصَدْرِ دَابَّتِكَ
“You have the greater right to the front of your riding animal.”
The statement starts with the owner's entitlement. Before accepting the offer, the Prophet ﷺ made clear that the person whose animal it was had the primary right to that place. Only after the owner explicitly assigned it to him did he ride.
For example, a friend's car, book or seat should not be treated as freely available merely because of friendship. One may accept a freely offered place with thanks, but the act does not erase the owner's underlying rights.
The lesson neither requires refusing all kindness nor licenses taking another's property as an informal privilege.