Gold build not functioning as expected? (740k gold with 11 Light Purses)

I'm pretty new to the game and after beating it, I tried endless mode with Lotte.

I'm currently on Endless Mode 10 and I don't understand why my damage is as low as it is doing a Sand Dollar build. I have 742000 gold, and 11 Light Purses (increase all dmg by 1% of current Sand Dollar amount). I read this as increase damage by X% where X is 1% of Sand Dollar amount, but it's possible it means increase it by a flat amount (X% of Sand Dollar amount). Even in the second scenario, I should be adding a flat 8162 to my base damage, yet I am hitting for just over 8500 with crit. And this isn't accounting for an 8-plank missing Light Drill, or the other 20 trinkets that increase damage by a percentage.

I am still killing bosses pretty easily, but I was expecting to fully break the game with either a 8162x modifier or even a base damage of 8162 that is modified by Old Pirate Hook type items.

If it matters, I am using hooks as my ammo and also used moneybags for a long time with lots of purses.