Everyone acts like there is a cheater lurking around every corner. Some people are actually good at these games. Really good. And sure, some people use cheats. I was personally banned from several COD2 CTF servers back in the day, and I have never used a game cheat of any kind - not even on the original single player Doom. Why? Because my ratio was too high, or I got too many flag pulls, or whatever some bullshit reason was that an admin came up with. Unfortunately the admins can only use the tools available to them and I personally would prefer them to err on the side of caution. Hopefully, as Flush said, upcoming patches to BF3 will help alleviate some of this.
In the end playing games should be fun - that's the bottom line. If you can't have fun because you suspect a cheater is around every corner, you might need to re-evaluate why you play. Our admins are good what they do and they will get the cheaters sooner or later. Just hang in there and have fun.