I have never done it and in my pre baby days would have thought it terrible!
Fast forward to an isolated beach dd1 (3) in the sea needs a wee and I just took one look at picking up all my gear, drying her off, trecking to find a loo that probably filters straight to the sea and wrestling her back into a damp cossie, all while holding baby dd2 and told her to just wee in the sea.
When DH arrived and she proudly told him her special sea wee treat he said I WBU to let her.
So who IBU?