Is it normal my friend's work suddenly turns her on?

My friend has worked from home on an adult sex line for a number of years and recently told me she's been getting turned on during most calls, which until now only happened very rarely with a few callers who stayed on the line for extended periods.

Apparently most callers only last 2 or 3 minutes of dirty talk, then they come and hang up without even saying thank you.

She is single and intends to remain so, and isn't into casual sex in her personal life, not for any moral reasons but because she says it just doesn't work for her. She has a lot of sex toys and tells me she has an active sex life by herself and now also on line.

I think it's all fine and so does she, but I'm wondering what people not involved think of it?