Isn't that just parenting?
There is definitely one rule for my kids and another rule for the adults in my house.
As I am an adult, I am able to make decisions on what is best for my kids. I don't expect them to necessarily understand why sometimes in one set of circumstances I would do one thing, yet in a different set of circumstances I would do something else.
Life isn't black and white and we need to make judgements and I'm old enough to do that, they are not.
My kids are young enough to accept that, when they are older and they challenge me, like I used to challenge my parents, I will respond in the same way my father used to "whilst you're living under my roof........."!!