Long story short my grandmother raised me. After 36 yrs I met my father for the first time. The last twelve months my grandmothers mobility has declined so my father picks me up and takes me to collect her once a week. I support her to get her shopping whilst my father sits in his car. He charges her £30.00 and expects his lunch bought(not a sandwich). The trip is a total 70 miles he drives a diesel car and only pays for diesel so he has no other car cost. My father also charges her another £10.00 each time he goes to her house during the week (1/2 times 30 mile). Im annoyed as I feel he should only charge the cost of diesel which all in after using an online cost calculator does not come to more than £15 total. AIBU as annoyed that I feel he shows no gratitude for her raising me when he just walked away and charging her in this way. If we had another option we would take it but as I dont drive and have mobility issues myself I feel he is using us.