What you may be referring to is people with very very mild glaucoma and very little money that are on expensive drops like Lumigan and Travatan Z in some cases with very careful monitoring may be able to use the drops once every two or three days. I think it not a good idea and don't do it in my practice. If there's a money problem I recommend selective laser trabeculoplasty.
JCH MD
Dear Dr Hagan,
Thank you very much for the prompt information regards use of glaucoma eye drops.
Best wishes
Raymond Ricaud