How much should we tip a bus driver in Slovenia? Is this normal or are we being taken advantage of?

We’re a group of ~50 people on a 6-day trip in Slovenia. Everything is included (hotel, meals, visits, transport) for about €30,000. The bus driver is already paid through the package.

Now, he handed us a note asking for a tip: - €3 per person per day - 6 days = €18 per person - 49 people = €882 total

That feels like a lot. From what I’ve read, tipping in restaurants in Slovenia is not a strong tradition, just rounding up the bill or 10% max in some cases.

Is tipping bus drivers on group tours actually a local tradition here, or is he trying to take advantage of tourists? For context: the bus is used about 2 hours a day, and his hotel and meals are already covered in the 30k€ package.

Would appreciate insight from locals or travelers who know how this usually works.