It turns out your biggest challenge isn’t shoppers who complain, but those who don’t.

A report late last year from PricewaterhouseCoopers made this clear, and it’s worth taking a closer look.

Here’s how we reported this in SN: Grocery shoppers are less likely to complain about their bad experiences to company management than shoppers for other goods and services. Almost half — 46% of grocery shoppers do not report bad experiences to their grocers, vs. 24% of banking customers who do not report bad experiences and 21% of media/communications customers. Grocery shoppers are willing to share bad experiences with their friends, however — 92% said they do so, and about one-third of shoppers will share their bad-experience tales for six months or more.

This topic has big implications so I delved deeper through an interview with Paul D’Alessandro, PwC U.S. customer impact leader, and Shaivali Shah, PwC U.S. customer impact consulting director.

Why are grocery shoppers less likely to complain? These experts said food items are relatively cheap compared to items from other industries, like hotel rooms or flights, and they have shorter lifecycles than items like apparel or shoes, so customers often don’t think it’s worthwhile to put in the effort to complain. Moreover, it’s very easy to switch to competitive food outlets.

Grocers, of course, would rather hear the complaints than find out later when shoppers switch. So I asked the PwC consultants for some steps retailers can take to get more critical feedback (and of course positive feedback too), and I picked out four easy and effective ones:

1. Identify Who to Complain to. “With airlines and hotels it’s clear who to complain to,” Shah said. But not so much in grocery. Do you complain to someone in the store? To the manufacturer?

2. Add Simple Mechanisms: A simple concept like a kiosk at the checkout that asks customers to rate their experience could make a big difference, D’Alessandro said. A manager could get an alert to quickly visit upset customers.

3. Put Associates Front and Center: Place employees in the right places to get feedback. A retailer could turn a cashier into a greeter who interacts and channels people to shorter lines, all with little marginal cost, D’Alessandro said.

4. Target Social Media: If there are customers on social media talking up or down your brand, engage them, he added. Invite them to in-store events and seek their feedback.

My advice is to try these steps, and see if you don’t get more squeaky wheels coming out of the aisles.