If buying a pink gun aided in my wife shooting more, I'd have zero qualms in buying one. I think whatever it takes to get your family to do things together is a fine thing. One of the EXACT reasons I now own a .22 fire arm. It hadn't been inside the first 5+ firearms I've ever bought but now I'm glad I did with more to follow I'm sure.
She wants pink/purple ear protection instead of my black Browning muffs - done. Whatever gets her active into shooting. She's now starting to get her info together so she too can get your CCW license. Kudos to her as I've had mine for 6 years now. She has "her" XD9sc that I carry, but if she wanted me to paint something pink or whatever on it, consider it done.
"Snickering while you walk away" is probably the most honest answer somebody would give me as I'm quite "able" a man haha. I also have zero issues with shooting said "girl" gun and am secure in my abilities and am masculine enough.
In short, Smith found a part of the market that may have been un-tapped and made a small run that in no doubt will sell. That's why they're still around, keeping the money coming in the business.