Why is the UFCW opposed to Whole Foods

Currently UFCW aand other Unions are boycotting Whole Foods.
Whole Foods has a very generous benefit plan- a plan that years ago UFCW would have endorsed and fought for.

Now they appear to be opposed to such a plan and they are in favor of a government run health insurance plan.
They also seem to support the opting out of any current health plans for their members and seem to have no problem if the corporations that their members belong to opt out.(Safeway, Giant Food, Shoppers etc.)
Should this happen Union members who are now covered by their employers will be subjected to an inefficient form of health coverage that may even cost them more money.

Why would the Unions support such a plan?

How about this idea:
A few years ago there was talk that Royal Ahold could legally shut down Giant for a few days, change the name to Shop and Stop- and reopen as a non-union store.
For years the main grocery stores have complained how expensive their health premiums have become.
In order to cut their expense, they could become non-union and either offer a poorer insurance plan or none at all.
If they became non-union- the union would lose millions of dollars in dues. and lose some political clout.
Perhaps-- facing such a loss of members and dues(money) the Unions struck a deal with Giant(with Safeway and Shoppers etc. to follow), that they would support the opt out plan if and this is a might if-- the stores stay unionized.

Something to think about.