I was traveling solo, but had plenty of good advice from the locals on where to go in town. Evenings were great - I'd usually wander into the heart of town, stopping at a small restaurant along the way for a snack.
Seriously - one place makes the best Yakitori I've ever tasted. I stopped in there most nights for a pre-dinner snack.
I tried to vary where I ate each night, ranging from Chilled Soba Noodles to Okonomiyaki - a cross between pancakes and noodles - way better than it sounds!
There's a few bars in town, ranging from western style to traditional to karaoke. I was a fan of "Stay", which is a western style underground bar.
The town has plenty of public Onsens too. An Onsen is like a public bath, with hot water coming from underground natural springs. I was a little iffy about the whole idea, but as long as you can find a quiet time to take a bath, it's pretty nice.
Head on in, remove your shoes, and stash your clothes in an empty locker. You wash before getting into the tub - so as not to dirty the water for everyone else. Tubs are for soaking, not washing.
My first time in an onsen, it took me about 15 minutes to climb in. Seriously hot water! I lasted about 2 minutes before feeling dizzy and having to get out.
You get used to the heat though, and after a day tumbling down the mountain there's nothing better than soaking in a hot tub!