Tim Hortons

I'm becoming more and more frustrated with Tim hortons, every time I go it's something... today I was I drive thru ordered a large 4x4... got to the window handed her a 5 dollar bill and she very rudely said it's 6.80 I said I only ordered a large coffee, she then scoffs at me and says oh... then she hands me a large coffee which is marked reg so I then said I ordered a large 4x4 so then they go make it during this time I had asked several times for my change... she says ya I'll get it... you should give a customer there change right away... I love Tim's coffee but Iam growing more and more frustrated everything I go there it's something and not just that location ALL of them... thank you in advance...
Sincerely
Tara