Retail Legal Dilemma - what would you do?

Here is a situation which I would like your opinion on.

You are at a department store going through a stack of specials on cosmetics and skincare.

One stand in particular has a sign on the top:

"50% off, prices as marked"

You pick up a body lotion, original price $20.
It is marked at $14.
It scans at the register for $14.

There are many of the same body lotions on the same stand, so the line item has been placed there deliberately by the store staff & not accidentally moved around by customers.

FYI: Legally, you are entitled to have that item at $10 because the "50% off" overrides the "prices as marked".

Knowing this, I'd like to know what you would do.

1. Would you ask the sales assistant (SA) for the price to be reduced to $10?

2. If the SA says "it was a mistake" or tries to fob you off, would you insist on the $10? Maybe even ask for a supervisor?

3. Would you leave it & walk away on principle?

4. Would you buy it anyway at $14.