Why the public transportation in Netherlands is so expensive?

I’m traveling on vacation with four people and we pay almost 40 euros on bus only to travel to a place and back in ONE day. How do you live with this kind of prices?

[Edit to add context: Was in Hague. 4,5 euros per person (x4) one way ticket. The round trip was 36 euros. The distance was between 6/8 km to the city centrum. We used a regular bus line.]