If you get a lot of dishes like we do I'd say around 500 baht per person. No booze included, though they do have some nice cocktails too if you want. We do order a lot and share around. But it is excellent food, staff and premises. They do have a couple glassed in air con rooms as well you can use. We go there for special times, like we do at the Haku Zou restaurant as well (which actually is a bit cheaper). It's not a weekly place to go really. There's a ton of other places we can/could use, but right now these are not as Covid 'friendly' places in my humble opinion. Tried the White House recently. Would have been fairly inexpensive, but I wanted to try one of their steaks, which was 1 K baht in itself. But with their Thai dishes, and a couple large Heinekens, the bill would have been around 1K total. I'm waiting for Dome to reopen the Hippy House restaurant. Love their food and quite cheap actually, even adding in a couple beers. Many places are not up to par these days as well due to small customer base and Covid. If I find a place we like I stick it into our family night out rotation.
By the way, who is 'they' that say? I find it reasonable for what you get, the venue itself, extremely attentive staff, no drunken louts about, and its close proximity to home. If we want to save money on dining out we will usually hit one of the many restaurants in Robinson's Mall.