I like to do both! All my warbirds are from kits and my stunters are now mostly ARF's. Having built for 20+ years I really enjoy it and build the airplanes I want to make to my satisfaction. Stuff thats just for drilling holes in the sky is where ARF's for me fit right in. As example in the last six months I built a TF P-47 1/5 kit and assembled a GP Little Toni and Skyshark Christian Eagle. I now am building a TF P-51B 1/5 and assembling a glider ARF. Frankly, I dont buy the "I dont have time to build", the real point is that for many building is not a priority use of their time as we all make time for what we really enjoy. The big difference I see, not always but often, is when most people crash an ARF the agony is minimal, which is fine, and with a call to Tower can get right back into flying within a few nights or so. When my Toni splats on the ground at 120mph I will cuss one time then laugh, when the P-47 augers in I will need half a dozen Martini's and a visit to the shrink. The other big difference is that most people that havent built a few planes couldnt come close to duplicating an ARF in quality or looks never mind price. So for many of the folks "raised on ARF's" building would be a big step down, and unless they want to really commit to learning to build they have no reason to do so. ARF it, build it, buy it RTF who cares as long as you enjoy the hobby.
KirkRC