I'm at the tail end of the generation and am surrounded by these people. Maybe it's different geographically. But the effort to type two words is usually easier than finding that special camera app you might have (plenty of people still don't know what app they need to read the codes).

QR Codes might be useful for a complex URL with some sort of novelty behind it; a prize or whatever. But your brand shouldn't be that hard to find.

It's a Facebook sign. Get them to use Facebook to find the store. Same goes for Twitter. Accessory apps are a hurdle.