Dry burgers - unfair sauce pricing

Is it just me or is R6 for extra sauce daylight *******? A Chrunch Burger is R27.90 and to add extra sauce they charge R6.00 - just to make sure their burger is not dry which it usually is. So if we buy a few burgers and add extra sauce on all of them the price is more than an entire burger! I wrote to KFC as the sauce price jumped from R2 to R5 and now R6 in 2-3 months, but they did not even deign to answer me.