I don't view that as gullible, I view that as a perspective that is incomplete due to geographical circumstances. And I am sure that's probably a road that goes both ways, with people in urban & suburban areas not seeing the full picture with respect to rural society.
https://www.cato.org/publications/tax-budget-bulletin/reform...
To put that in context, the GDP of the state of Iowa is $173B. And that's just one state with a large agriculture sector.
However I'd also like to comment on a common argument that Blue States/Cities pay for Rural areas. Yes, red states receive a disproportionate amount of federal aid, but that is something everyone benefits from. For example, farm subsidies keep food costs low for everyone in the country. Low income states with a high proportion of people on SNAP & other means-tested government programs mean the social safety net is improving our society as a whole by ensuring fewer people are left behind, which would be an even larger drag on society & the economy. In short, I don't think you can separate funding by state in that way and come to any value judgments based on it because the interwoven nature of our society means we do not stand alone as individual states.
And that's why I said:
Not bad people, but gullible people.
Because the political and cultural interests of rural areas are different than the interests of urban areas? The economies of rural areas have crumbled. But 50% of the population live in cities and so economic policies that benefit the "majority" of the population will completely miss the issues rural areas face. Trump's support is because he at least pretends to care about them.