Slightly off-topic, and yet relevant to anyone facing the same dilemma: Now that I’ve baby-proofed all of my outlets… how do I plug something in?
If you have already separated a nail, or two, or generally jambed-up your fingers trying to remove one of these things, then you know what I mean. If not, then wait until your firstborn is crawling, you’ll discover that outlet covers, carefully designed to keep stuff out of outlets, really do work!
There are even patents issued for devices to remove them (tip #2: don’t use a knife, if that is your solution, then you should install them even without a toddler in the house).
The trick is simple, don’t take it out the way you would expect to, i.e. by grabbing top and bottom and pulling the prongs straight out. The designers have thought of this and rendered it futile. We’re trained to unplug things using this technique because otherwise we’d bend the prongs, or potentially zap ourselves. Instead, go for one edge, and pry it out from side to side. You have a second class lever working for you this way. It may take one or two wriggles side-to-side, but definitely no pain.