As a protest?
As others have stated...thems are the rules, so what would the protest be protesting?
When I holiday (that's when family are present), I want them to have a 150% better experience than I.
I fly regularly and can live without a lounge and if I'm with my kids, the last thing I'd even consider is hovering in a lounge whilst some of my family is waiting in the reception (presumably patiently) for me to fill up on average food and grog. I cannot see the protest there. All I can see is unjustly hurting a child and running the risk of the unimaginable, a child going missing.........forever. How would anyone sleep in that scenario.
Please all, I could strangle my kids at times (well OK, most times), but let's not start foolish hypotheticals that some idiot might just try. As much as I personally believe the lounge dragon in the OPs case was "over the top", there is no protest to be made here except fly with someone else.....don't use your kids as pawns!