Some square speed bumps have a square form factor, wedge shaped sides over here so that if you aim with the bump right in the middle of the car, sufficiently wide-tracked wheels are on each side, negating the bump, presumably for emergency vehicles and buses to not be concerned with the bump.
Obviously obnoxious SUVs and the like are impervious to this, obliviously driving over. Conversely, a chat with my local mechanic turned up an issue with unprotected engine underside (like with most cheap to mid-range cars) means there's a sufficiently higher chance to rip the oil drain plug, meaning slightly increased tow-in rates with each new speed bump. Nasty, although more recent cars have undersides now in an effort to reduce drag and improve compliance with emission regulations.
Obviously obnoxious SUVs and the like are impervious to this, obliviously driving over. Conversely, a chat with my local mechanic turned up an issue with unprotected engine underside (like with most cheap to mid-range cars) means there's a sufficiently higher chance to rip the oil drain plug, meaning slightly increased tow-in rates with each new speed bump. Nasty, although more recent cars have undersides now in an effort to reduce drag and improve compliance with emission regulations.