I'm looking for pressure sensors up to 22 kg and more. So far the highest capacity I could found was 25 lbs. Do higher ones not exist?
Your problem may be that you are using sub-optimal search terms. The kilogram is not a unit of pressure, but instead of mass. Scales technically do not sense mass, but instead sense force. This is assumed to be the force exerted by a resting body under earth gravity. Pressure is force over an area, such as pounds-per-square-inch (PSI) or the Pascal which is a newton per square meter.
Anyway, the sensor you want is called a force cell. The nice ones are rated in newtons or kilonewtons, with a kg being equivalent to 9.8 newtons.
Here is a load cell that take up to 50 kg. http://www.phidgets.com/products.php?product_id=3135