I don't know about the tow truck side of it, but from my side, I've never had the experiences you have had.

I had used their towing from time to time (once every 2-3 years, maybe).  When I've had to call, they contacted the tow truck and sent them out; and I've never got letters about rate increases.

Frankly, I've had to go to the AAAPlus membership.  The basic AAA covers towing only in the first 3 miles, and that just doesn't cut it for me.  So, I've gone to the the next level.  I've thought about other companies with similar insurance, but have never switched.  Different times I have wondered whether AAA is worth the cost; however, it comes down to a "peace-of-mind" issue - it's good to know I can call them if I need.  And I guess that is worth the cost.