Why are sleep/lock the same thing?

Question

So, I have read all the common complaints about the iPhone and happily, it seems like people tend to agree on most of them and that they can be more or less easily solved by a software upgrade. But there is one thing I think is SO annoying and I am worried because I have not seen anyone else mention it. Thus, I am concerned that I am the only one who thinks it's a problem.
I find it very annoying that sleep and lock seem to be the same thing. That is, when the screen turns off, the phone also locks. I understand why the screen turns off - so power can be conserved, but the fact that this makes the phone lock is so annoying. Every single time I look at the phone, which might be a 100 times per day, I have to press a physical button to wake it AND slide the bar thing.
On most phones, locking is an option. You can implement it when you need it. Why is it not that way on iPhone? It just seems to me that the screen should turn off after a minute or two and then you should be able to wake it again just be touching the screen. If you wish to lock the phone, that should just be an option, not the default.
Does anyone else agree with this?

Answer 1

I did send feedback, thanks for the link! If other people agree with me, please send feedback too! Again, I'm not saying that a lock feature shouldn't exist, or even that automatic locking shouldn't exist. I just think it should be an option you can turn off and on. That way people who are worried about making accidental calls, or people who are using the ipod function, can turn on automatic locking if they so choose, and people who don't want automatic locking, like me, can turn it off.
By the way, is making an accidental call, etc, a danger with this phone in the first place? Doesn't it only respond to human touch and not to being touched by things in your pocket/bag? It seems to me since this phone has no physical buttons it is more or less totally immune to the normal candy bar phone problem of accidental calls, etc.