Absolutely no discussion of inflation is complete without recognition of the fact that inflation and inflation expectations are at
historically low levels[1] right now. Economists aren't arguing that we should inflate our way out of debt--they are arguing that we should return to the historical norm. Of course, it's possible that these economists are secretly just pushing inflation as the "hidden tax" we're all up in arms about. But I find this unlikely. I find it far easier to believe that most economists actually believe that moderate inflation is
good for the economy.
Why do economists believe this? Prices are sticky, and some prices are stickier than others. Prices for labor are especially sticky, which means that when growth expectations fall, it's very difficult to decrease wages, which in turn makes it difficult for supply and demand of labor to balance. In the Cliff Note version, inflation helps because people are willing to take real pay cuts when they're disguised as a nominal pay increase. There's a vicious cycle during a recession, where falling output causes the price level to fall, which in turn causes more imbalance in the labor market.
It's important to recognize that the standard argument for inflation has literally nothing to do with "the government printing money to pay for things." Does the US government make money from seignorage? Yes, it does. Is it a significant source of income? No, not in the context of US government spending or revenue--it's roughly $30 billion dollars a year. Are these crazy inflationary economists suggesting policies that would increase seignorage to a significant level? No, they're not.
Finally, most of these arguments are disputed by the so-called "Austrian school" of economics. It's important to recognize that this school is much, much, much more popular with laymen than with professional economists. This doesn't mean that the school's arguments are wrong, but it does raise questions about why the school's arguments which seem so utterly convincing to so many people, don't manage to gain many converts among people who research the subject professionally. Once again, I don't find "conspiracy" a particularly good argument.
[1] http://www.clevelandfed.org/research/data/inflation_expectat...