Except the average person sees the exact same benefit, ideally. It's the same platform William Jennings Bryan campaigned on way back in 1896 - expanding currency helps people who have debt.

Inflation makes the past matter less. It erodes both the wealth of the super-rich and the debt of everyone else (the farmers who had to mortgage their farms in 1896; the normal family now who has a home mortgage as the norm). That's very attractive to a lot of people, not just those managing the national debt.