That's so true! These days if you go through a Babysitting agency your bill will look something like this:

Registration: $20 (that you pay the first time you hire a sitter, it's a once off thing)
Petrol/transport fee so the sitter isn't out of pocket getting to your place (usually round $10)
$18 per hour or more after midnight or if you have more than one child
You have to provide meals.

This is for an experienced and police checked sitter. They are usually highly capable but as you can see it costs for the peace of mind! DH and I once attended a wedding and it cost us over $150 all up for the babysitter.... that was back in 1997 though... no doubt fees have risen.