I'm going to take a rather subjective approach to this...
You should find another Dealer for servicing. Not because the Techs took the vehicle out for an unreasonable distance (which I don't feel was unreasonable at all), but because you don't have firm trust in the facility.
Trust is very, very, important. If you don't trust the people working on your vehicle, then they could be doing all the right things, even being altruistic and you still will feel that you're being mistreated. It's human nature.
I completely understand how you feel about someone else working on your car. Coming from a family who did all their own work, always, it took me a very long time to find a mechanic I could trust. I've finally found a Local Independent Mechanic I can trust. It takes time.
You want to find a Mechanic that you can trust... And often times, it's a Local Independent which will provide that. They have less overhead, less middle-management, etc... Less hands in the pot. For complex issues, yes, Dealer Techs are a much better idea, buy for most of the common Automotive Issues, an Independent is going to be likely cheaper, and higher quality level of care. One issue with Independent's is that their Customer Service might be a bit rough around the edges... Personally, I'd rather have someone be a bit less polished, but be honest and fair rather than have a fancy waiting-room and lip-service.
So again... Highly subjective stuff here.
The best way to find a quality mechanic is to ask around. Ask friends, neighbors, etc... Ask, ask, ask. You can check local review sites like Google, Yelp, YellowPages, as well. Find one you feel is a good fit, and take your car for a basic service, and see what the experience is like. If something rubs you the wrong way, then just go back to the drawing board. Simple as that.
So in conclusion, while I feel that the Techs didn't take your vehicle for any concerning length, I feel it's more important that you're confident that the folks working on your car CARE! I completely understand how you feel, and I urge you to look into other options if your feelings for this Dealer don't seem to improve.
I hope this helps.