I grew up shopping in regular American supermarkets, like Shop-Rite and the A&P. Ethnic markets were treated as oddities by outsiders, where you went for strange meat innards and bizarre canned foods.
Then I moved to a ZIP code that's nearly 80 percent Latino, and while there is an Albertsons, a Ralphs and a Vons within reasonable distance, my closest stores all have Spanish signage in the window. I couldn't be happier, frankly, because while I do still need to go to gabacho grocery stores for some things (ahem, buttermilk), the bulk of my weekly grocery shopping happens in the Mexican market.
My local Mexican market is Northgate, which I love for its outstanding "Rancho González" produce section and its meat counter, but these tips go for almost any Mexican market: Vallarta, El Super, Superior, or just the local mom-and-pop shop.
1. You've been overpaying badly for produce.
How much is cilantro at your Safeway? A buck a bunch? Well, at your Mexican market it's four bunches for a dollar, and it's the same freaking product. Peaches? Half-price. Chiles? If you buy just a couple, they usually won't even charge you, because it won't register on the scale. But it isn't just that the produce is cheap–Mexican markets are a treasure trove of things that can be hard to find in regular markets, like fresh bayleaf or avocados that are ready to go.
2. No one buys Mission or Guerrero brand tortillas.
The tortillas at your Ralphs are on the end-cap near the dairy fridges; they're Mission and Guerrero brand, which are essentially identical, and identically awful. Walk into your Northgate, though, and buy fresh from the tortillería. Eventually, though, you'll discover that they also sell masa para tortillas for under a buck a pound and tortilla presses for $10 or so–and that's when you'll swear off that GRUMA nonsense forever.
3. The meat counter is an experience all on its own.
Waiting at the meat counter in a gabacho grocery store is depressing. There's rarely anyone there; you have to press a buzzer to summon a butcher, and chances are they'll just point you to the shrink-wrapped meat in the display cases. Not at a Mexican market, though; Mexicans don't trust shrink-wrapped meat. The carnicería is a bustling, busy place, often with music playing and a barker calling out numbers (and telling the occasional groan-inducing joke).
4. There isn't much bottled salsa.
The larger Mexican markets may have a small display of La Victoria or Pace salsa tucked away next to the mole and pipián pastes. It's for gringos who can't handle the salsas made fresh every day at the deli counter, and who don't have abuelita at home grinding chiles, tomatoes and garlic in a molcajete. The one exception, though, is canned El Pato sauce, beloved of Mexicans, pochos, and savvy gabachos alike.
5. The cash register impulse-buy "gauntlet" is completely alien.
As you walk up to the cash register in a gringo grocery store, you'll be tempted by racks of trashy magazines and huge displays of Hershey's-type candy. There's some of that at the Mexican market, but there's also Mexican candy, from De La Rosa mazapán to Pelón Pelo Rico push pops. In the more traditional stores, you'll see a plastic display case full of candied fruits and squashes, sold by the piece or by the pound… and a rack of Picot antacids for your overindulgence.