There is a sizable group of veterans who call themselves the "Patriot Riders" and most of them, but not all, ride motorcycles to military funerals and other body escorts in case there are protestors around. These guys don't openly carry weapons, but I know several with CCP who would be packing. They normal routine for them is to surround the funeral area with their presence and will "take matters into their own hands" to make sure the funeral goers are not bothered directly.

 

As Bears Butt indicated there is a group called the Patriot Guard Riders who attend most if not all Military Funerals. Here is a link to a video that may help describe what you have witnessed. These folks just basically keep the protestors blocked from view of the members attending the funeral and have at times helped remove folks who protest military funerals.

Additionally the wishes of the deceased military member may have requested a full honor guard and gun salute in addition to replicating the time they served in the military if discharged under honorable conditions or retired. Once someone has served in the military honorably you can request a Military Funeral and with full honors again if you specifically stated when you pass what your funeral arrangements are to be.

 

They were not patriot riders but active duty marines. Curious if the patrol guards are for combat veterans.

 

I recently attended a funeral of a former Marine (jar head) and I was pleased to see all the bikers lined up the street there must have been 50 of them there was also an American flag standing up by each one of them. It was amazing and worth seeing. Once the funeral was over they all got on their nice bikes and rode off. They seemed to all have a patch sewed on their vest with their military signia.

 

As of late military funerals have become a place for crazies to raise their hate/misgivings towards military/government etc. There have been threats of causing mass injury/death/panic at these events. It is becoming more and more common to have armed guards/LEO's present at the funerals for that purpose. Hopefully they are never successful in ruining one. The world is in a state of chaos and this is one way to insure final respect and peace is given to the family/friends of a fellow brother in arms. Unfortunate that it is necessary, but the crazies out there make it this way.