Shocking behaviour from a 19 year old! We live an hour from an airport, and while I could use an Uber, Taxi or train to get there, one of our adult kids will drive us and pick us up, for free. It won't even be a discussion. We do lots for them, so I'd be annoyed if one of them even gave a heavy sigh in response to an airport pick up request.
You've got to deal with this in two ways, firstly the disappointment chat. Even if she already knows what you're going to say, do it again, make it long and boring. She must also pay the money back and pay the difference between the agreed price and what the Uber or Taxi cost was.
Then, there's the moving forward with an adult part. With this level of entitlement, I'll be shocked if you're not paying for her phone/gym/toiletries etc at the very least. All of that stops NOW! I wouldn't throw her out or change the locks, I'll always help my children with what they NEED, but any extra stops. No washing, no cleaning, no cooking. I would provide the basics only. There would always be cereal, bread and noodles in the cupboard if she had no money, but apart from that, she would be taking care of her adult self from now on. I would let her think that this is permanent.
You've said this is out of character (I'm not convinced), so if it is and she repays the money and starts taking care of herself, then I would probably relent on some fronts a little way down the track (at least six weeks). But, I'd pick and choose. For example, sometimes it is just easier to cook for everyone or throw on a load of washing for someone else, but, she would need to cook at least one night a week for the family and she would need to throw on washing or vacuum on a regular basis too.
If she's working, and as you say, bad with money, down the track, I'd definitely be charging board, even if you save some of it to give her when she moves out (don't tell her this). You might decide that 100 a week will cover food and toiletries, her share of the cleaning products etc. But maybe put half of that in an account for her when she moves out.
If she's heading to uni, the loan probably doesn't cover everything, I'd be reducing the amount you said you would cover to top her up. This one is a little more tricky. You don't want her dropping out because uni life is miserable, but you shouldn't be funding party nights out of good cuts of meat. Even if it's just for the first term, she needs to see that adult privileges and freedom come with an equally important balance of responsibilities.
I suspect she's had a pretty nice life and been well looked after, but she needs to see the consequences of her actions. Further down the track, if you have spare cash, you 'may' choose to make her life a little easier again, but by then, hopefully she understands a bit more about being an adult and is ready to appreciate all the things you've done for her.
If you don't toughen up on her, she'll be headed for a fall at some point, because she won't be ready to deal with real life as an adult. Toughen up now, so that she'll develop into a better human.