30psf isn't actually in the list of SMPTE standards
Implicitly 25psf has been used for years in Europe for film material where 24fps film has traditionally been shown at 25fps. The 4% fater running time is just accepted as normal, the sound pitch likewise or it can be corrected.
The US has suffered badly from its standards. 59.9Hz fouls up timecode for the prodcution people. 3:2 pulldown fouls up transmission of 24fps film. This can be overcome with advanced standards converters. These can convert 24Hz material to 30Hz without significant quality loss. They can also recognise and remove 3:2 artefacts.