Going shopping, whether for groceries or general merchandise, is very much a routine part of everyone's life. People that haven't worked in the types of stores that they shop in usually exhibit normal shopper behavior. They look for an item, ask around if they can't find it, find what they're looking for and take anywhere from one unit, to potentially cleaning out the shelf. Those are just some of the usual shopping behaviors observed within grocery retail, as well as other potential retailers.
However, when someone has worked in a certain retail setting as I have, they tend to look at the store setting much differently and behave according to that view. Some of the less anticipated acts are usually considerate of those that are working during the time taken to shop.
1. You tend to "block" or "face" when taking product.
To do either of those things simply means pulling something forward. For those that stock (or fill) shelves, or do a lot of blocking (or facing), this is especially applicable. On your day off, you might see something that's out of place, and cringe as you quickly walk past it (slow walking is frowned upon, as you've learned).
The best advice I can give to anyone that does this is "have your brain clock out." What I mean is that you might associate a certain setting or place with a working mode. Because of this, you feel the need to move or be productive at random. By "clocking your brain out" you manage to relax in the process (especially if you get stressed out at work).
2. Walk the extra distance to put something back.
Whether it's a cart or a refrigerated item in a dry grocery aisle, if you've worked in retail before, you may find yourself trying to put the item back. You understand that the little things you do, in those aspects, make it easier for associates, and reduce waste.
With your experience, you've likely been inconvenienced with the placement of items. You might commonly hear the phrase "they get paid to put it back." Though this may be true in some job descriptions, your ongoing effort to put things back where you found them is indicative of your occupational background.
3. Be more polite to store employees
With knowing the struggles that retail associates deal with, whether it's an overbearing manager, or the routinely rude customer, you usually go out of your way to make the days of those associates a little better. Your inclination may be toward being more pleasant and trying to lighten the mood for the employee.
After gaining experience in the retail environment, you'll find that you're not the average shopper. You behave differently, (in some ways perceived as odd by normal consumers) and that's okay. Without a doubt, any retail clerk that interacts with you will have a boost in their day.