I have tried half a dozen round, collapsing silicone bowls and have found that, when bumped or lightly pressed along the rim, many of these bowls will collapse, spilling their contents all over the counter, even when they have lids on them. I did find one mixing bowl that did not collapse easily when in use.
I bought it on Amazon and it has a hard rim with a small indented pouring area. I suspect that the shape and consistency of that rim is what stabilizes it:https://www.amazon.com/Squish-Mixing-Bo ... xing+bowls
However, recently, someone on the forum (I can't remember who and can't find the thread again) directed us to a video that recommended a product called "Thin Bins" for use in the cooler. I ordered a set from Amazon and they arrived tonight. I am pleased. When the lids are on tight, they appear to be air-tight and they did not collapse, even when I pressed fairly hard. When the lid was off, it was difficult to make them collapse, even when they were empty.
I'm guessing that the shape, with the corners, must be part of the solution: https://www.amazon.com/Thin-Bins-Collap ... containers
Footnote on the above Thin Bins: You don't slap the lids on. You use the attached clips and clip the lids on. If you slap the lids on, they can collapse down to the food level.
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Not a bowl or bin, the collapsible dishpan also works well and doesn't collapse until you want it to:https://www.amazon.com/Prepworks-Progre ... HR2H2C6782
When workable solutions are found that help us when we camp, we should share them in camping secrets, to help others. I hope this helps you!