It's not unusual.
A lot of 9v/12v chargers for all manner of things run at different ampages.
( Kroney, Wed 28 Nov 2012, 11:05, 3 replies, latest was 13 years ago)

still shit, universal leccy for all

( Naked Ape call me Caitlyn, Wed 28 Nov 2012, 11:06, Reply)

Ugh, I'm getting sucked in again.
Smaller motors can get burned out by putting a high ampage through them. Therefore the batteries require a lower ampage, therefore the charger requires a lower ampage.

Different computer equipment also requires different power levels. Also, Dell might not want you to use an HP charger. So they rate their equipment at a different level.
( Kroney, Wed 28 Nov 2012, 11:08, Reply)

it's a laptop, not a car!

( Naked Ape call me Caitlyn, Wed 28 Nov 2012, 11:09, Reply)

I have literally no clue as to how you've managed to get to adulthood
without having the first idea how the objects you use every single day work. You and swipe should have a chat about how wondrous and magical all this witchcraft is.
( Kroney, Wed 28 Nov 2012, 11:13, Reply)

I know other stuff instead

( Naked Ape call me Caitlyn, Wed 28 Nov 2012, 11:18, Reply)

Like?

( tangledupinblue hairy badge with moving eyes, Wed 28 Nov 2012, 11:20, Reply)

STUFF

( Naked Ape call me Caitlyn, Wed 28 Nov 2012, 11:22, Reply)

How supermarkets work.

(PsychoChomp, Wed 28 Nov 2012, 11:22, Reply)

bit slow today

( Naked Ape call me Caitlyn, Wed 28 Nov 2012, 11:23, Reply)

And here is the point where Nakers can no longer understand anything you say and asks increasingly stupid questions until you walk away.

( tangledupinblue hairy badge with moving eyes, Wed 28 Nov 2012, 11:07, Reply)

that's seems a little unfair
why is electricity different up here in Hertfordshire? London electricity charges my laptop just fine
( Naked Ape call me Caitlyn, Wed 28 Nov 2012, 11:08, Reply)

Alright 'Tom Jones' that's enough.

( Monty Boyce, My cheese game is strong, Wed 28 Nov 2012, 11:08, Reply)