I remember back in the day 675 was only for emergencies as stated as a condition on the license. Also, the GMRS licenses were issued with mobile call signs, mine was KG something (three letters and four numbers). Somewhere during one of the periods of the renewal processes mine was changed to my current license WQJT335.
I also remember back in the mid 70s that Orange County React was very active on CB channel 9 and used 675 as an intercomm link amongst all the React Monitors. I can't remember the guy's name now that had a scanner and cb store on Euclid in Anaheim he owned one of the first mountain top GMRS repeaters on Santiago. I believe it was the 675 repeater that React used. I think his name was Bob Neal. He was very instrumental in promoting radio communications as a hobby. If it wasn't for him I may not have gotten knee deep into this hobby with the scanners, CB radios, and now GMRS. I never got the HAM bug for some reason and today I still don't and probably never will.
I bought a ton of scanner crystals from him for my Regency ACT 10 channel scanner before Radio Shack came out with the synthesized scanner or was it Bearcat that had the first synthesized scanner?
I've had my GMRS license since the mid 90s and dabbled in mostly simplex use. Before I moved from Northen California 4 years ago, a friend owned a repeater on a mountain top and gave me permission to use it. I never really did use it although, I did programmed the channel in my company car and maybe used it a couple of times.
It wasn't until I moved to Arizona, I noticed that GMRS was very active and most of the repeaters were either restricted or closed systems for Club members. So, I decided that I better join so I can get in on using the repeaters and the fun. I'm glad that I did.
Now, I have several mobiles, a bunch of portables, and now a repeater station. I guess, I am infested with the GMRS bug and I hope there is no cure for it.