Why dont city buses give change ? Is it like giving a tip or helps make up for discounted rides?

Because drivers are NOT allowed to have any money on them.

Does anyone have change for a dollar? That always work

Scotland do not do this.

They drive a bus. They aren't cashiers. I took buses in NY in the 70s and 80s and they didn't offer change back then either.

they used to some year ago, the bus drivers had a change device on their belt clip and dispensed change and it was very fast,

City transit districts and private bus companies don't want their drivers robbed.

First and foremost, that exposes drivers to unneeded danger. Anybody with an actual soul is going to avoid that.

Second, while the money that might be stolen is small spuds, the cost of settling a lawsuit from a bereaved family member is enough to daunt even the most soulless of those you sometimes find at the tops of organizations.

They usually offer cards with a value that will deduct the correct value when used or worth a fixed number of rides. If you use the bus often, you should look into that.

Possibly OCD.

Time consuming

they probably just dont carry change around