We use a collapsable one similar to this in our MR2.
Folds up and out of the way when not in use.

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We use a collapsable one similar to this in our MR2.
Folds up and out of the way when not in use.

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That doesn’t look like it would hold any more bagged groceries than the Toyota accessory cargo tote.
I‘m hoping to find something that can use at least 50% of the available trunk floor space to hold grocery bags in place so they don’t tip over and spill the contents.

 

There out there, just need to know the dimensions of what you want vs what will fit.
What about building a tray the size you want out of 1"x 6" ( or 8") pine with a 1/4" plywood or masonite bottom.
The Home Depots of the world will cut the boards to size for free and you can glue or screw it together.

 

Look on Amazon. They have cargo totes with feet to prevent sliding in the trunk. I don't really use the trunk unless I have lots of bagged groceries or something large and flat.

I use my back seat for minimal items.

YMMV

 

I don’t use the back seat since I do curbside pickup of groceries and the store staff just drop the bags in your trunk. When I get home, I’m collecting the cans and bottles that have spilled out and have been rolling around in the trunk.
I want something that takes advantage of much more of the available trunk space than the Toyota cargo tote accessory, but obviously isn’t so big that it doesn’t fit.

 

Do you have a weathertech cargo liner in the trunk?

The collapsible cargo totes I see on Amazon looks like they have no way to prevent sliding in the trunk. But, if you get multiple ones with dividers that may help keeping it weighed down.

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We've been using curbside pickup also from Fry's / Kroger. They have been putting the groceries in paper bags that don't seem to move much. Perhaps you can complain when they send you the after pickup survey. Those plastic bags are useless.
In normal times we just use our own re-usable bags that we bought years ago - the newer ones are not very good.
Had to replace the thin bits of plastic in the bottom of those bags with some thin vinyl sheet from home despot.

 

I load my trunk with bear cans so it holds my things in place