I typically buy duty sized guns. I like big, comfortable shooting, intimidating looking handguns. Most of them see range or HD use, but I carry them around often as lifestyle and dress allows.
That said, on vacation, I'll be packing a little LCP stuffed into my cargo shorts pocket. Too much crap to cart around for my wife and 4 year old to bother with another couple pounds of handgun on my hip. However, it's the only "compact" gun in my rotation. My SP101 is concealable, but it's a heavy brute. My full size FNH pistols are thinner than a Glock, but they aren't what I consider ideal for the IWB role. The same thing can be said about my Beretta and 1911s. They're robust.
I still think there is a very good use for a Mouse Gun like the LCP.
There is no doubt the buying public prefers these tiny monsters. You really have to commit to wearing 30-50oz of gun on your belt. It's way easier to drop a single stack micro in your pocket or purse and be done with it.