And you're in a state with no income tax, where housing costs are comparatively low and so mortgage interest is also below average?  90% of my clients don't itemize, but that's because most of them are old enough to have paid off their mortgages. Is the 8283 putting them over the standard deduction by a couple thousand, so it's not worth IRS time to audit for an adjustment of less than $500?  

You do know, I hope, that IRS can do a preparer project and pull a list of preparers with too many clients filing one type of deduction too often.