If you select the information (i) icon on a coin room before entering it will show you which tees you'll be using before entering. This will either say Tier or Hard.
Tier tees means that you're going to play from the tees assigned to your tier, and Hard means that each player will play from the same tee.
From your description, it sounds like you're playing in those rooms with Tier tees.
Also, on mobile we see a lot of players who only play in head to head games, and never touch a ranked round for some reason or another. Since coin rooms do not count as ranked rounds, their average doesn't drop.
For the first few tiers we have specific levels that will push the player to the next tier. This way their aren't any level 90 Hack players or anything like that.