Well thats fair enough,
I think you'll find its against money laundering legislation to accept cash for a bank draft, without the cash being lodged first to a bank account that identifies the person ordering the draft. If you ever see the film " The General " there is a scene where he walks into a branch with 50,000 cash and asks for a draft. Well the Criminal Justice Act 1994 was brought in after that and technically from then on you couldn't just buy a draft from a bank without the source coming from an identifiable bank account. If the staff member gve you a draft without being able to identify the source of funds, they could end up in big trouble. If you managed to get one before then they were bending the rules, but in this environment I'm sure bank staff are crossing the t's and dotting the i's to avoid losing their jobs.
You should try internet banking, there loads of things you can do online, especially if you live in a rural area.