Google Express currently has no membership fee. The minimums are different per store, around $25. What keeps Amazon my default is with almost every Express order I have some item cancelled by to store. (And the excessive taping and packaging of each item.)

I prefer shopping for Walmart in Express, because Walmart.com includes third parties with ridiculous prices and quantities, and also in-store only.

My most consistent use of Express is for Costco quantities of organic canned beans and bags of organic rice.