It's there so that you can create a junk account for apps which want access to your credentials? Doubtful. Remember the context of the topic.

This thread started with:

"It's pretty crazy that you need to use the same credentials to "buy" a $0 app as you have to remotely lock and wipe your iphone and mac."

I'm having no trouble remembering the context. Why are you?

Everyone I know with family members tries to share a single login across all devices to share purchases.