Perhaps it's a personality thing, but I find snarky or scathing comments about my work entertaining, if they are witty enough, and at times they are instructive. Also, some of them are so transparently absurd I find they give me a good laugh (for example, I've had people review my otherwise well-received gothic mystery horror/thriller novels with comments like "too scary" and "too disturbing", which is like criticising a comedy for being "too funny").