Hi there! The benefit of having a medical cannabis recommendation is that it allows you to shop at medical dispensaries. Right now, a lot of cities/counties are not yet ready to go with recreational dispensaries, and so many dispensaries are still operating as medical dispensaries. To shop at these they still require a medical cannabis recommendation.
In addition, if you are interested in applying for your state issued MMIC to receive a tax break on your cannabis, you need to have a recommendation to apply for one. To do this, you need to take the recommendation you have, and apply with your local county.
We wrote an article not too long ago on this topic. You can check it out here: https://www.hellomd.com/health-wellness/5a302030100a820006562ebf/why-youll-still-need-a-medical-recommendation-after-jan-1
I hope this helps! :)