I think that some of this stuff lies in the calculated perception of risk. "Our" generation was raised with "Stranger Danger!" (actually I think I had a board game by that name, nice friendly concept, right?

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When the reality is that your child is so very unlikely to be hurt in any way by a stranger that he's actually MORE likely to be struck by lightening. Meanwhile, the very REAL risk factors people tend to ignore.
For example, I've noticed that people are using Florida's horrible car seat laws to take the opportunity not to bother with car seats or boosters while on their vacation...and yet...the number one accidental killer of kids in the US? Car accidents, almost always due to improper or lack of restraint.
So....statistically speaking, a 22 month old child who rides in an FAA approved child restraint on the plane, and then rides rear facing that same restraint in the rental car, and spends an evening with a background cleared trained care provider is statistically less at risk of ANYTHING happening to him on vacation, then, say, a 22 month old who rides as a lap child, doesn't have a car seat, or uses something suboptimal (forward facing car seat, booster seat) in a car, and stays with mommy the whole trip.
It's all about perception of risk. The actual REALITY of risk does not bear out the common perception
Like I said, I would probably not leave a non-verbal child alone with a single care provider, but people do it every day (home day care for example?) and the children are incredibly safe.