I know its been done to death on here but I view paying for a TR as pay to fly as-well. If 10 candidates go for an interview with 5 places available, it would be the biggest coincidence in history if the 5 best candidates also happen to have 30000 euros to spare.
I reality some of the 5 who eventually get the job were probably outclassed in the interview/sim-assessment(but obviously still made a required minimum grade) by others, but the others had to admit their bank account balance has a minus in front of it and therefore are not able to take the job!
Thus HR move down the list to find someone who can pay.
If this happened(or starts to happen!) in any other industry, there would be riots on our streets.
Paying for a TR and hours might go but paying for a TR and job is not
