"Blonde ambition" is when brunettes think that blonde hair will make them more attractive, therefore they spend money on highlights and other salon products to become blonde.They are not satisfied with the hair color they were born with and have low self esteem about their generic hair color.
Brunette-"Hey I would like blonde highlights"(God I can't wait to be blonde, maybe now (Name of random guy) will look at me!ie. blonde ambition.
Salon Owner-"That will be $40.
Prices shown in USD.