... you shouldn't assume 'rights' over someone else's?
I have a friend who passed her driving test four years ago. In that time, she has never bought a car, as she 'can't afford it'. She has, however, taken several expensive holidays, redecorated a couple of times, bought a laptop, an i-pad and an i-phone, and paid off £700 debts that her son ran up at Uni.
She frequently asks me for lifts and to run errands for her, using the phrase 'it's easy for you, you've got the car'. I don't, however, take expensive holidays, redecorate, own an ipad, iphone, or a new laptop, or pay off other people's feckless debts.
I own and run the car because I prioritise that above other things, not because I'm wealthier than her - in fact, theirs is a two-wage household and mine is not.
Perhaps 'assuming rights' was the wrong phrase to use but I find myself increasingly narked, not be doing the favours for her, but by her assumption that she can choose not to run a car because mine is available to her....