We used to do similar to MP and give DSD $50 a week to pay for all her clothes, phone, movies, public transport etc. etc.

For that she was meant to go to school, cook dinner once a week and empty the recycling bin.

She barely ever did all three and we ended up docking some or all of her pocket money each week. Then she would bug her friends for money and/or steal from them.

Extreme case though. I still think giving teens an allowance is a great idea and will teach them invaluable budgeting skills.