My mind is sufficiently boggled

Found here

My dear friends that I've referred to in previous posts are having their first baby and I have been invited to their baby shower!  This is the first "friend" shower that I've been to and I'm a complete and utter n00b.  We checked out several places they've registered but, as she's already had three showers thrown for her, most of the items on her registry are already gone.  This in and of itself is okay as myself and a few of our other close friends are going to go in on a present together.  We decided on a car seat - easy enough, I thought.  I was sadly mistaken.

For instance, did you know that:

• You need a "base" along with the car seat.  Apparently the seat itself is not adequate to hold the baby as you go barreling through the suburbs.  Also, you should buy TWO bases, for both you and your spouse's cars.  The bases, that I saw, were $85 each.  EACH!
• A car seat can fit onto a stroller.  However, you may not want the stroller that fits with the car seat so you would then need a separate stroller
• Side note on strollers - If you plan on jogging or running with your baby in a stroller, you can (if you are so inclined or if someone is kind enough to gift you one) get a B.O.B.  It's a $500 stroller.  Just for jogging.  It also has a seat that can detach and fit into another "base" that can go into your car.  Of which you probably want two.  Does it ever end?!
• Car seats apparently don't grow along with your child so this first one we buy will only last for a few months.  My friends will then need to switch to a different car seat.  I am unclear on whether or not you need to switch bases as well
• Car seats have tents.  W-T-F...
• Apparently, I've only scratched the surface regarding babies.  What other things do you need to know??