Yeah I'll say. If it's humid at all after something is blasted you can stand there and watch it rust. If somebody isn't powder coating something after it was blasted it will need extra thick paint, vs something you just prep sanded. A paint gun is a must, to me anyway. A spray bomb won't lay enough volume down and rust will start fairly quickly. The type of paint matters too. Dad was out of enamel for his gun one time after he blasted a flywheel for an old stationary engine so he grabbed a rattle can of flat black barbecue paint to put on it temporarily. He said it was just as rusty the next morning as it would have been without any paint at all. He told me the rust looked a bit different though. Had a fuzzy hazy look to it like frost would. So that's how good barby paint is for protecting something.
will quickly rust if not protected.