Originally Posted by HoustonConsultant

All passengers are required to be able to follow crew members' instructions, and during boarding it will be apparent that an unaccompanied 2 year old cannot do that.

Some people want to fly from A to B as cheaply as they possibly can. United responded to that demand by offering hugely restricted (yet not wildly different that Southwest/Spirit/etc) fares.

United even puts up big pictures and graphics when you are trying to buy these very restricted fares.

However, none of that protects United from the stupidity/laziness/ineptness of us, the flying public, so now we are mad that they did not proactively program in restrictions that do not allow people to purchase a particular ticket if someone in their party is below some age at which we'll all disagree.

I know it shouldn't have gotten this far on this flight, and undoubtedly the kindness of strangers would have (and did) rule the day, but if United had this restriction, we already would have seen the "United is discriminating against families" post here.