It can, but if its done right, it will be fine. Concrete cracks..that is a rule of life. Cracking doesn't necessarily mean a failure. Concrete crack failure is defined as a crack that a US nickel can be inserted into..on edge of course. Steel mesh and or rebar, on no more than 12" centers each way with a 2" off the form perimeter bar, will hold it together as long as the cracking isn't catastrophic. If the use fiber in addition to the steel, even better. Fiber alone is wrong. Fiber is an admixture designed to augment structural reinforcement and prevent random cracking, not a stand alone structural reinforcement. Plus, they will be using better mixes for precast, or at least should be. 4000psi or up , maybe even a 650 flex mix or High Early. That gives you a stronger, more durable product.
As to placement, that is why they should be placed on at least 2" min of loose material. Small rock, say 3/8" and under, or sand. Before placement, you should smooth it out to get rid of hills and valleys, place the pad, wiggle it a tad and you are good to go. It will settle down and be solid.
In my experience, cast in place would cost more. You have to buy enough forms to make it cost effective to use readymix ( usually 5yds plus) or balance out cost of bag crete. Ground has to be leveled and prepped, forms set, steel set and place and finish...lotta steps and time for a single tee. These guys can prep and pour in mass with reusable steel forms and then deliver. You just prep ground, add your loose fill and set. Done. Less steps in the field which is where one incurs higher costs. The company being able to pour and finish multiple pads at once and all in the same place cuts cost for them by a large factor, thus a cheaper end product delivered. They don't have to have finishers spread out over a whole course getting the pads poured and finished, so...less labor is needed. And all you need is 2-3 people and a bobcat to set them.