all that transactions had Gas Price 5000000000 Mwei along with 21000 Gas used, i.e. each trn had 0.005x21000 = 105 ETC fee, all fits. so it's not a ETC network bug, it's just a strange behavior of wallet's owner (or somebody who accessed it).
Yes, you are right. Thanks you.
Can you feel anything fishy about these below addresses?