Of course there's nothing wrong with having standards ... we ALL have them. We just don't all have the SAME standards, or put the same level of importance on certain standards. I may feel strongly about eating in a healthy manner, but not care less about what the kids watch on TV for example. If someone else comes along and thinks I'm a crappy parent for not caring what they watch on TV, yet they know nothing about me and the rest of my high standards, that's what I don't like. The one thing they are picking me apart for is just one small part of my overall parenting package. You can't expect me to be "perfect" at everything!
Not to mention when you screw up - some people would flog you for it! Maybe they have never screwed up in that way before and cannot imagine it, but what have they screwed up that we don't know about? No-one is perfect, yet I find people judge each other so quickly over just ONE aspect of their parenting, which we all know is a very complex business!
When I think of some of the things our parents did and didn't do, and compare it to how most of us turned out, it makes it very clear that good people can be raised under less than "perfect" conditions. Having standards is important, but you cannot live up to every single possible good standard perfectly - some have got to slide some of the time, or you'll drive yourself crazy! We all have different challenges in life, and what may be possible for you to accomplish as a parent may not be possible for someone else, at least not at this time.
And as for trying to be the crappiest parent .... that's just people finding their "weak" spot or the few areas they've decided can slide, and coming to terms with them by finding humor in the situation. You just can't take yourself or your life too seriously!