Polygonal viewport results in significantly larger PDF

Hello everyone. I'm trying to save my DWG as a PDF, and for the most part there's no problem. However, if a drawing uses a polygonal viewport instead of a rectangular one the resulting PDF file size increases drastically.

A 500 KB PDF (using a rectangular viewport) becomes approximately 38 MB when using a polygonal viewport. We use Bullzip PDF Printer as our printer/plotter.

I've seen very little discussion on this topic. This post only mentions it as an issue. No solution to be found there.

Thank you for your time.