Why do so many parents co-sleep with their baby?

Do you do it for the convenience of not having to get up with your baby in the middle of the night? Or are you just to lazy to deal with trying to get them to sleep in their own crib etc.. I don't get it, what am i missing here?
Or do parents just not understand how dangerous it really is to have a infant sleep in your bed?
And then you wonder why they keep posting "how to get my baby to sleep in his/her bed?" Don't you think it might have something to do with all the times you co-slept with your baby?
NOT TRYING TO BE RUDE , I JUST WANT TO KNOW WHY?

Baby is Measuring 35 Weeks?

I went to the OB yesterday due to cramping, OB said baby's head is way too Low, I'm dilated 1,and she said my cervix was "paper thin" she put me on bed rest with legs elevated…Is this because she thinks labor is around the corner??

When You Put Your Baby To Sleep, Do You Keep The Room PITCH BLACK?

do you turn ALL the lights out? I usually keep a night light on but have seen several posts that say when putting baby to bed turn out all lights. What do you think or do and WHY?

Does anyone have any tips on how to get a restless baby to sleep>?

he is 11 months old…he just started this…i rock him, pat him give him a bottle and pacci and do the sssshhhh ssssshhhh sound in his ear…he closes his eyes but he kicks, moans, rubs his eyes and takes forever to stop and finally sleep…then he wakes very easily…I have tried baths before bed, tylenol because he was getting some teeth and i thought that was it…Does anyone else's baby do this..any more tips?

Where and what does your baby sleep in?

We are expecting in November and I am trying to get my head around all of the bedding options. I know for the first couple of months she will sleep in our room. Do we need to get a cot from the beginning or will a moses basket last her for a couple of months. So many decisions, what is your experience? Oh and we are sort of short of space so I don't want to end up buying things we rarely use. xx