Google Shopping and CSS: Why are brands still overpaying for clicks?

Google Shopping should be one of the most efficient ways to win new customers, yet many retailers are still spending more than they need to.
If your Shopping campaigns are eating into margin or your cost-per-click (CPC) keeps creeping up, you’re probably paying for clicks that don’t convert.

In this article, we’ll break down why this happens, how to stop it, and how CSS partnerships can dramatically cut wasted spend, while improving performance at scale.

The Hidden Cost of Poor Optimisation

Even the strongest products and brands can overpay for clicks when small inefficiencies build up across their Google Shopping setup.
The most common culprits? Unoptimised feeds, weak campaign structures, and poor bid control.

It’s rarely one big mistake. Often, it’s lots of small ones adding up.

1. Business Strategy and Website Performance

Google Shopping can’t fix an uncompetitive website.
If your prices are higher than your competitors, or your checkout experience is slow or confusing, even perfect campaigns won’t deliver strong ROI.

Before you invest more in ads, ask:

• Is my site converting at an acceptable rate?
• Are my prices competitive in Shopping results?
• Do I have products that simply aren’t profitable to advertise?

Improving your conversion rate means you can afford to bid more aggressively, or, if you work with a CSS partner on a CPA model, offer higher commissions to drive more visibility.

Premium CSS partners like Redbrain use this insight to help retailers focus ad spend where it delivers true incremental value.
With experience across 35,000+ retailers worldwide, our teams quickly identify where websites are underperforming and how to fix it, whether that’s improving site speed, product relevance, or pricing strategy.

2. Google Shopping Set-Up: Getting the Foundation Right

The two things that make or break your Shopping performance are:

• Your product data feed
• Your campaign structure

Unlike Search Ads, you can’t choose exact keywords to target in Shopping. Google matches your feed data to what users are searching for. That’s why accuracy and structure matter.

Product Data Feed

Optimising your feed reduces wasted clicks and lowers CPC. Focus on:

• Clear, keyword-rich titles and descriptions
• High-quality images
• Correct pricing and availability
• Proper product categorisation (using Google’s 6,000+ product taxonomy)

If your data isn’t clean or detailed enough, Google will misplace your ads, and you’ll pay for irrelevant clicks.

At Redbrain, our AI-powered optimisation platform processes over 2 billion products daily, refining product data automatically. This not only reduces costs but ensures ads appear for the right searches, at the right time.

That’s how we help our partners generate over £1 billion in annual product sales through better feed optimisation alone.

3. Campaign Setup: Smarter Structures, Better Control

How you structure your Shopping campaigns determines how efficiently your budget performs.
The default setup (one campaign with one ad group)is quick but costly. It gives you almost no control and forces the same bid across every product, regardless of how they perform.

The Fix: Tiered Campaigns and Ad Groups

Create separate campaigns for Brand and Non-Brand traffic.

• Your brand campaign captures loyal customers searching for you.
• Your non-brand campaign reaches new shoppers, without overpaying for brand terms you already rank for.

From there, build multiple ad groups for high and low-performing products. This allows for:

• More accurate bidding
• Better visibility into performance
• Easier identification of low converters

Without segmentation, you’ll end up raising bids on entire groups, paying more for poor performers just because a few products happen to sell well.

That’s where Redbrain’s machine learning and Smart Bidding come in.
Our system automatically adjusts bids across thousands of products in real time, improving efficiency and cutting waste without increasing workload.

4. Campaign Management: Keep it Constantly Optimised

Google Shopping isn’t a “set and forget” channel.
Pricing changes, stock fluctuates, and competition shifts hourly. Without ongoing management, your campaigns quickly drift into inefficiency.

Regularly review:

• Product group and ad performance
• Auction insights and bid simulators
• Product pricing and availability

Even small changes, like a competitor dropping price by £1, can completely alter your position in the carousel.
Successful retailers monitor performance daily or work with CSS partners who do it for them, using automation to stay ahead.

At Redbrain, our teams use real-time data and hourly bidding adjustments to keep campaigns lean, visible, and cost-efficient, without retailers needing to manually tweak settings every hour.

So Why Are Brands Still Overpaying for Clicks?

In short: because most don’t have the time, data, or tools to optimise at scale.

For small retailers, that might not matter much. For large or growing brands, it adds up fast. Thousands of clicks, millions in spend, and untapped revenue left on the table.

The simplest fix? Work with a Premium CSS partner that operates on a Cost-Per-Acquisition (CPA) model.
You only pay when a sale happens, meaning your spend is automatically aligned with results.

It’s how Redbrain has helped retailers across Europe turn wasted ad spend into incremental growth.
Our results speak for themselves:

• £1BN+ in annual retail sales delivered
• 20% average CPC savings vs. Google Shopping EU
• Thousands of retailers now scaling profitably through CPA partnerships

If you’re still paying for clicks, you’re paying too much.

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