We have a few LBS in my small resort town and I don’t think any of them sell bikes anymore. Demos and rentals are huge here along with service and gear/supplies.
I have my shop I go to all the time. Have never bought a bike from them because well they don’t sell bikes. But they do have probably the best mechanics in town and are great people. I get all of the stuff I need right away from them: tires, lube, tubes, gloves, etc. I bring them coffee, lacroix, sometimes beer, pizza, you name it. It’s a really great shop. I tell everyone to go there.
I don’t really ask for much in return despite usually getting 10-25% off pending what I buy and my repairs in a pinch usually get put to the front. Though, I always bring my bike down usually within a week or so of when I need it back for whatever race. So, I always say, just need it by X day.
So, building a relationship with the LBS is a great thing and encouraged.