Why would someone who isn't from Philadelphia do this?
An announcement location is about crafting a narrative. Barack Obama announced his 2008 campaign at the Illinois State Capitol because he began his political career there as a state senator and it fit with his overarching message of, "Middle America is working even when Washington isn't."
Hillary's 2016 "kickoff event" (there was no announcement event since she announced via a YouTube video) was at the Four Freedoms Park on NYC's Roosevelt Island. It combines Hillary's adopted hometown and the state she represented in the Senate with an island and a park named after a president who shifted his party to the left and redefined Americans' "conventional" notions of what obligations the government has to people. It was a way to preempt the ascendant left wing of the Democratic Party at a time when, as with FDR, poverty and income inequality were major issues in public conversation.
Unless you can craft a narrative around Independence Hall, there's no compelling reason to use it for an announcement unless your campaign is being run by a fourth grader who skimmed through his social studies textbook.
In that case, why didn't Ted Cruz announce at IH? He was all "Constitution" this and "Declaraton" that and "Founding Ideals" that. While I agree with the sentiments, it is still odd he didn't announce there with this logic.
The Declaration of Independence and the Constitution are two different things...
And you don't have to be physically present at some building/city where one of those things originated to show you want to "defend the Constitution" or whatever. I mean, that is such a generic premise for a campaign narrative. Is there anyone running for president who
doesn't care about/like the Constitution?
Per Wikipedia, Cruz announced at Liberty University. That basically fits in with his original intention of being the "Faith, Family, Freedom" candidate who was going to win all the Southern states on Super Tuesday and be propelled to the nomination.
That didn't work out. Instead, he ended up being the candidate of the Great Plains and Upper Midwest whose campaign made no sense unless he was running in 1936 as an opponent of the New Deal.
