Costco and Bimart are two very different business models. Both are "members only discount stores", but the membership only requirement at Bimart is more of a token things, and rarely enforced. $5 for a lifetime membership? That's nothing. It's a token charge that allows them to compile a list of shoppers for advertising purposes.
That's really what the Bimart membership is about- advertising. The $5 lifetime family membership fee is absolutely nothing to them in their business model, whereas to Costco, their $120 per year fee adds up to some real money.
I haven't been asked to show a membership card at Bimart, at any location, in many years. The only time I've pulled it out at all is for the rare return on something like a car battery core.
I always have my card out, or wifey has hers. Walk in the door, holding it up, button gets pushed and we walk in. Easy peasy. Sometimes, there's one of "THEM". The ones that "I've never had to show my card!", or "Oh, OKAY, snarl !!!" They look and act like spoiled kids when they get huffy, digging through their purse. I'll always use my card, because I'm not a spoiled brat. And generally there's people filing in in front of you and behind you. Having the card out keeps the line moving. It's simple. The store would like you to buy a $5.00 card that gets you in for life. They would like you to show it to enter. Seems pretty easy to me.