Payslip is PnC no matter what the reason for the interviewer/recruiter to look at.
No HR will give their employee detail to other company. That just plain dumb.

Teach? i was never asked to include my pay slip But i did stated my current salary inside my resume.

I dont have to proof anything to the HR. I they dont believe me dont hire me. Simple as that. I've have never been asked for payslip before in all my interview since 2001.

I do agree on HR not trusting ppl due to a lot of new age worker tend to 'adjust' their salary but have less working experience or certs to backup the amount they stated in resume.

But with their years of experiences in interviewing ppl they could easily filtered out any too good to be true candidate.
Asking for payslip is a rude way of telling "i dont trust your got that salary with the tiny amount of experience you have."

Peace