They can come with early payoff penalties. It seems weird, but a loan is a thing that can be and often is packaged up and sold. If you pay it off, they have nothing to sell. Resale value of your loan is a factor in how much it costs.

Asset-backed securities are a strange world of value based on value that can either lead to market collapse (because someone misvalued them, see 2007-2008) or market efficiency (because more people can afford debt for stuff).