I've done that for a few forums and gaming sites to discourage myself from wasting time there. A lot of people used to trade lists of marketing domains for addi

I've done that for a few forums and gaming sites to discourage myself from wasting time there. A lot of people used to trade lists of marketing domains for adding to their hosts files before browser plugins were created for the same purpose. It is not an uncommon practice and should not bother anybody unless they suddenly need to access one of these sites from your computer, which can be easily fixed for a short time.