I did an Ulta shop years ago, probably like 5 years. It was easy but more involved than the fee/reimbursement warranted. I think it was somewhere around $5 reimbursement and $7 fee.
I love Ulta and used to go there for my hair color. My stylist knew that I mystery shopped and told me that they do get mystery shoppers but I have never seen one for hair. I did do a mobile photo audit at Ulta but it was just taking pictures with no purchase necessary.