Hello,
Are you in the Provincial portion of your return?
Provinces have different tax credits and benefit programs, where for example Ontario would use the amount of Property Taxes or Rent you paid for your principal residence to determine the amount of Ontario Trillium benefits you would be entitled to, if any. In Ontario's case they request the Role number associated with your property tax bill. These benefits are income dependent and diminish as the applicant's income increases.
I cannot answer for why other preparers did not ask this information from you before.