I've seen those "net" type tire straps come out from behind a tire that's a bit too small.
One thing I've seen that I've never heard of coming loose is to loop a strap through each wheel, then ratchet-down the crap outta it. Some guys also go so far as to attach an additional strap to something on the chassis or a solid suspension-piece at each end of the car, "just in case". It goes without saying, that any edge inside the wheel that the strap passes-across, even if you don't think of them as "sharp", can possibly cut through the strap.
You never know when something's gonna happen, and the more secure the car is, the less-likely the outcome will be bad:
http://www.facebook.com/photo.php?pid=31003553&id=1178283885&l=9849072ab4
Car, trailer, and truck came out of this OK, so Mark sez. You won't hear any argument from him about strap-overkill, I bet.
-Scott Creech
F-Stock Bullitt Mustang; OMRSCCA
Parfois, on fait pas semblant