Baristas again

Here baristas were mentioned in some of the comments.

I’m reading “The Falls” by Ian Rankin at the moment, and have come across this:

‘Not often I see you smiling,’ his barista said as she made him a double latte. Those were her words: barista, latte. The first time she’d described her job, she’d pronounced it ‘barrister’ which had led a confused Rebus to ask if she was moonlighting. (page 24)

Obviously, not only is this a Scot (I think we can assume that she is) who is new to the word barista, but also one of the increasing number who are less than fully rhotic!