See, I wouldn't mind that. I have a key to my moms house {essentially my home, too} but I would not ever just let myself in. I respect privacy that much.
I know of two people who gave their keys to their mom/m-i-l and did not count out them dropping in at any time.
When my friend told me I was flabbergasted.
I would like some one to have a key to my home in case of a lock out. I have seen my neighbor lock herself out quite often and while I'd love to offer to keep a key for her {as she always comes to borrow my phone} not being close neighbors it would be odd.
*sigh* just remembered the days when we could sleep with just the screen door shut. And it wasn't a metal security one. Okay, it was the 60's....