"Half price on..."

[MackerelOfFact]

This really winds me up when I got into shops. Huge signs saying "Half price on all Herbal Essences Shampoo and Conditioner" or "Half price on selected vitamins and supplements". (Boots seems to be a particular culprit).

Surely it's "All Herbal Essences Shampoo and Conditioner Half Price"? The "on" doesn't need to be there at all.

"2 for £2 on X" and "Buy one get one free on X" are a bit annoying too - surely it should be "2 X for £2" or "Buy one X, get one free". But "Half price on" winds me up the most.

Tell me I'm wrong.

Go into shops, obviously.

It means "there is a half price reduction on Whatever". They're missing the reduction word, that's all.

Maybe it should be 'Half price for ..." ?

can't say its ever bothered me.
(BTW, do like your name, OP )