There are some things I love doing with my friends that I know they cannot afford to do on a regular basis. In particular, I love going out for a big sushi dinner every once in a while. This type of meal is often cost prohibitive for my "big eater" friends as a single roll/order of sushi can often be $10 for something that isn't particularly filling.
So, being the friend I am who also loves to spend time and eat with my friends, I often offer to treat my friends to the meal. However, this usually creates a bit of friction between me and a few of my friends who are averse to being treated. Responses are usually things like "Oh you don't have to" followed by them not wanting to go, them begrudgingly agreeing, or thinking they'll "owe me one". From one friend in particular, I feel as if he thinks this is a way of me asserting a form of financial dominance over my friends which is far from the truth.
For reference, during the dinner, there is zero tension from what I can tell and most people feel a lot more free to order what they want and try new things; it seems to be a genuinely fun experience for everyone once the whole cost aspect is gone.
Also, I usually (attempt to) treat my friends to something like this once every two months or so. Between these dinners, we often get together to do inexpensive things that everyone can afford to do frequently, so it's not like this is the only thing we do together.
Sometimes I've phrased this event as a celebration when I can ("Let's go out and celebrate your new job, Chadsworth! Sushi's on me!") and it's worked fine. However, it'd be pretty obvious if I always found an excuse to make it a celebration.
How can I treat my friends to this somewhat expensive (~$200-300 among 3-5 people) dinner and avoid/mitigate awkward interactions?
I'm mostly looking for good ways to pose the event to people and ways to mitigate potential misunderstandings/misgivings over the offer.