All jacks will need to move a little bit, as when lifting a long object from one side, it does not go straight up, but with a slight arc. Floor jacks with wheels move so they are always centered properly under load. Bottle jacks don't do this. When lifting a car with a lot of suspension travel you are at a real risk of the jack tipping and jumping out from under the car. Just hope you aren't under it if/when that happens.
My history with jacks is as a structural mover. I've worked with everything from 1 ton bottle jacks to unified jacking systems lifting entire hotel buildings on the beaches of Miami, Florida as well as the moving of the Cape Hatteras lighthouse in North Carolina.
Sure, bottle jacks are cheaper. I have five or six in my garage right now. I will never use one to lift a car.