Correct. The alternative to pounding fish oil supplements is simply stop eating so much refined seed and vegetable oils. A ratio can always be fixed in at least 2 ways obviously.
Ditto for "shelf-stable" foods. Omega-3 fatty acids go rancid at room temperature, so many packaged products have had the omega-3-based fats removed so they'll last longer on the shelves.
Source: my wife, who has a PhD in nutrition.
> The results show a little more of the healthy long-chain marine omega-3 fatty acid forms known as EPA and DHA in farmed salmon than in wild salmon.
> [..]
> “Indeed, there is a larger amount of omega-6 in farmed salmon. You get nine times as much as when you eat wild salmon,” says Research Fellow Ida-Johanne Jensen at the Norwegian College of Fishery Science.