Why are some Parents so anxious about their children riding the Bus?

I don't have an issue with my son catching the bus, infact he was adamant he wanted to ride the 'yellow bus' to school like the other kids did in our neighborhood. I let him, on the first day of Kindergarten and waited for him at his school just to make sure he was ok and he was. Mind you our bus stop is the first stop in the mornings and the first stop after school ,and its only 5-7 minutes away from the school too, so that could be why we haven't had any issues thus far.

I understand the anxiety of your child riding the bus. I think the bus system has become so ridiculous since they introduced it fifty years ago. I do not believe younger kids should be riding with older kids and I do not believe the people who run the Transportation want to address this issue because it would just mean more money for more buses. I have tried the bus for my kindergartner and I just can't let her ride with older kids. Transportation's answer to this is "Well, sorry that is YOUR problem." I don't think sitting in the front of the bus makes any difference - she does have ears and they work! I'm just going to suck it up and figure out a way to get her to school myself.

i have to say that i let my daughter ride the bus home, but not to school. i drive her..#1 we don't wake up on time.
#2there is the issue of space on the bus in the morning,( she is the second to last stop) and attitudes of the kids, they take up the whole seat or are saving it for a friend, the bus monitor does nothing and she had to beg to sit.. coming home she's one of the first on line to get the bus so a seat is never an issue.
in our local news, there was a story of the bus driver leaving some after school program , 4th -6 th graders,
on the wrong side of the street, before the after school program opened.. the kids were found wandering around.

a few times in sudden bad snowy weather,in one of the hilly communities, the could not get the children home, and they sat at the foot of the hill, because cars were coming down sideway's, the bus was stuck till 8pm, and not all the parents were able to go out in the snow to retrieve their children. i always have my daughter show me her bus route, in case i have to find her on a day like this. her cell phone is in her back pack.
my friend's 7 yr old was tormented on her bus the other day by another 2nd grader saying "i'm not gonna invite you to my birthday party" the girl ignored him untill he then said." i'm goning to tell the principle your'e ignoring me" the monitor didn't separate them, and the little girl was hysterical when the mother took her off the bus, mom then called the bus company, the bully's parents and the principle..
my daughter's first few day's coming home on the grammer school bus, some boy was teasing her and hitting her over the head with his book bag... she told him to stop, he didn't, the bus monitor didn't get invoved, so she slugged the kid in the nose. it should not have to come to this, but if no one is monitoring the kids ,this is what happens.

so i guess lack of supervision is the main concern here.
as is adhearing to weather reports, and road closures during inclement weather.

also i would never let my kid go on a class trip out of the area.. why? because the bus somehow alway's breaks down and kids stray and get lost. there was a class trip to NYC, last spring, and the teachers said before the show they'd let them walk about some. needless to say a number of mother's didn't sent their kids, so they had a play date.

Lack of supervision (one person that is driving and focusing on that, simply cannot manage a bus full of kids).
The lack of supervision leads to all of the 'issues' that have been described here and since my family is in a position to take kids to school and pick them up (Thank God) we do.