used to have same thinking as you.

but nowadays girl side's mother cincai:
give birth also 4k,
confinement center 7k,
study degree 10k,
house buffet before actual day 5k,
need to buy the daughter some gold necklace and bracelet 3k.

so 15k dowry is kinda justified, heck im marrying this year and giving my MIL 20k as dowry.

unless both of your parent side dont wanna do any ceremony at all, just go ROM then gaodim.