vote with your feet. If the prices go up, don't buy the items there, they will eventually loose money and reverse the price hikes. Mind you, there will certainly be some large yellow stickers screaming "CHEAPER, was xxx, now xxx" to make it look like you are getting a bargain.
I noticed the increase too, did a super shop online at Superquinn instead which had loads of good offers, raided the "reduced to clear" shelves at Tesco and Dunnes and bought the rest at Aldi. Tesco can stick their higher prices up their derrière