Why not? It’s easier than a character with an actual personality and background. Imagine how hard it would be to pretend you’re Brad Pitt from Fight Club when you’re on the trolling end of a wrong number text message. The fuck do you say aside from the usual “Hur durr NO RULEZ IN FITE KLUB GUISE” and “Me like soap” ?
Pretending to be Jake from State Farm on the other hand…well for all we know Jake is a convicted sex offender who spends his weekend coating his entire body in mayonnaise and fondling himself while watching reruns of Family Feud. Guy’s a blank slate. Do whatever you want and as long as you throw in “This is Jake from State Farm,” you’re golden.