While many bikers love wearing their motorcycle patches, sometimes there are reasons other than fashion for adding them to your jacket. One reason you might add specific patches to your vest or jacket is for identification. It's important for you to be easily identified as belonging to a specific motorcycle club or as holding a specific rank in that club, especially as certain events. As part of the club regulations, you may be required to wear a jacket or vest with these identifying patches at events and gatherings you attend as an official club member.
Some clubs have custom embroidered patches created that list the club name, its home town, and other facts about it. These patches are usually worn on the back of your vest or jacket. They make it very easy for people to identify club members or tell which club you're a part of at large biker events where numerous clubs are involved. You may also have a patch to wear on the front of your jacket or vest that features your name and the name of your club.
If you're an officer in your club, you might be required to add a rank patch to your jacket. These small sew on patches feature the title of your office, such as President, Treasurer, etc. They help identify who is in charge of the club. At large events, this can be very important, especially if there's a problem. Handing these patches out to officers is also a nice perk for doing a job that usually involves a lot of work and not a lot of thanks or other compensation.
If your club doesn't have its own patches, you may suggest it look into having some made at your next meeting. It's a great way of showing solidarity and unity.