> why don't they simply choose not to offer their services to Uber?

You assume there are other options without barriers to entry. You’ve learned how to drive uber, you’ve got a vehicle and payments to make - now take a risk on some other gig with a million unknowns?

Now it’s possible that uber cannot shoulder this cost by lowering their margins, and it will pass directly to the consumer as you suggest - but it’s not guaranteed. The fact that uber is behind this suggests that they can shoulder the cost.