Not trying to
but I honestly don't see how doing what OP has suggested has ANY impact on anyone in line behind them. Whether it is OP taking the picture alone, or if OP is bringing in kids for the picture at the last second, it changes nothing at all. Everyone behind OP will still have to wait the same amount of time. I'll never understand why people get so charged up at what other people are doing when it doesn't have an impact on them. MYOB
If OP were suggesting this for an attraction that has capacity, it's totally different as that increases the wait time for everyone else. But one photo impacts nothing, regardless of who is in it.