And that is exactly it. Evenly distributed between hands, feet, sit-bones.
On newer bikes from the shop, the tendency is to have the bars too high. There's a dozen reasons, but none of those are relavent. The point is that if your sit bones hurt, they are taking too much of the weight.
The solution is either to move some of that weight to your hands and getting proper core engagement by lowering the bar (assuming it is a reasonably proper distance.) Too high bars also often cause hand/wrist issues because the core is not properly engaged to support the body.
The other option is getting the feet to support some of that weight by adjusting the seat height or pressing harder on the pedals. Usually (counter-intuitively) that often means raising the seat to properly engage the leg muscles for good stroke. The result is less pressure at the sit-bones.
Good luck.