Why do all records with URLs appear as e-resources in the OPAC?
The presence of any URL in the 856 field of a MARC record causes it to display as an electronic resource in the OPAC, regardless of what the URL links to. This is a known issue that CUNY's Aleph committees have opted to leave as-is.
There are no national standards or local best practices regarding the appearance of URLs in MARC records. Campuses decide individually how they edit MARC records and whether they want to delete URLs other than direct links to content.
Even if a local campus cleans up records so that only direct links to resources appear, there are still issues with batch loaded files such as the Coutts orders used by many campuses for print content. In the union catalog, it is possible that even if one library's record did not contain extra URLs another college's record would still display to patrons as the master record.