Original Member and FlyerTalk Evangelist
Join Date: May 1998
Location: Kansas City, MO, USA
Programs: DL PM/MM, AA ExPlat, Hyatt Glob, HH Dia, National ECE, Hertz PC
Posts: 16,579
In cases where coach is oversold operational upgrades are usually given at the last minute by just assigning those without seats to first.
In this case, if they had wanted to seat the family of six in coach (presumably they had no seat assignments) they would have had to reassign six folks from coach to first, then issue the family those six seats. This is obviously a lot of work for the agents, and it's just easier and much faster to put the family in first instead of starting to reassign seats.
I'm not sure why you think this is a PHL thing, I've seen similar situations play out in other cities, and even on other carriers, this is somewhat of a standard approach to dealing with coach oversells ...