Pocket money- what’s fair?

I give my grandchildren £1 a week. At first they didn’t think much of it but now they have saved it up and realise what they can buy they are grateful. I considered putting it up to £2 for the oldest one but realised the younger ones would want it too. It doesn’t sound a lot but £6 a week adds up! They also get money from their parents. I was very firm with my DS and said they had to have pocket money and start to learn the value of money. I’m pleased they are comfortable but it isn’t right for children to think they can have anything they want delivered by Amazon at no cost to themselves. I pointed out that before they knew it the oldest be at uni with no idea how to manage money. She wanted a new iPhone and had to pay them back for it. We were asked for money for birthday/Xmas.

I only give pocket money to myy youngest DGS his brothers now all work so I give him £4 every week,he gets the same from his mum my DD and saves £2 aweek from this,he has a tidy sum saved.
They have all learnt the value of money,if they needed trainers or certain clothes mum would give them what she could afford and they put in the rest if they wanted a certain item and it was over mum's budget.
When eldest 2 where at uni rather than pocket money I did an Iceland shop for their student digs they may have been low on money but they where well fed.