Where have you seen individual bar pricing at $4.50?
I agree this is at the higher end (Musashi bars at Coles are $4.50) and bars in general are in the $3-$4.50 range. However I don’t think it’s too expensive. They can be bought in boxes for under $4ea.
Anything under $3 is usually a low protein (10g) bar or really a muesli or other snack bar with a bit more protein (10g).