Sadly this does lie in costs to salons and even though it is now for all ages it is the laws of minimum wage that are preventing salons from seeing older learners as viable investments. Minimum wage is ageist, always has been and probably always will be, such is life! Everything boils down to the government and I'm sure many salon owners sympathise with your position, but their hands are tied, they are business people they have to take care if their business.
As for teenagers fresh out of school I agree some are as you describe, believe me they don't last very long! Hairdressing is hard work and for the most part for very little money. You have to love it and I mean really love it to carry it through! The 16 year olds you speak quite often don't finish the course and move onto something else, admitting it's not for them! Don't not go to college because of this preconceived idea about young people! I'm 24, I surround myself with hairdressers of all ages, trust me, the younger ones are often inspirational. They're fun, energetic, full of life, loads of ambition and oh my god so much creativity.
If you can't get an apprenticeship go to college, get yourself in a salon for day release, get yourself unpaid work, do anything you can to get yourself out there! Do bar work in the evenings if you need paid work, work seven days a week 14 hours a day if you have to. (I started a bit later than most, thats what i did, worked in a pub aswell) Don't give up on a dream because it seems a little harder to get there, you might just have to do it a slightly different way than you wanted.
You will get there
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