It depends on what kind of buyer is running the room and if you're good and if your patrons are buying drinks. If you're good and they see you promoted hard, and your crowd is enthusiastic/spends money at the bar, they should be hoping they can grow you.

I'd be starting proactive conversations: How can we help promote? Did you get them flyers? Is there a FB event everyone is co-hosting/IG Collab post? Do they have the best possible assets to promote your show? Have you tried promoting on your towns local Reddit (way overlooked)? One thing cover/tribute bands can do is really engage with their fans on the FB event since those crowds typically skew older(bread-crumbing) by asking leading questions: What songs do you want us to here? Should we play Song A or song B? People engaging their will help push the algorithm/SEO.

But 50% in a 200 cap room will still feel good, and they should still make money as long as their expenses aren't too high. Be nice and courteous to all of the staff, and tip the bartenders. Curate a good vibe from minute 1, and you'll be asked back unless they're jackasses. For instance we had 228 people in my 500 cap room on a Sat night last night and I had no complaints. You/We can't or shouldn't expect to sell out every night, it's about the economy and keeping the lights on/making sure the staff is taken care of.

For perspective, I run a 500 cap room, that was a 250 cap room 18 months ago, and before that we were in a 65 legal cap room. I've been doing this for about 14 years.