Reddit cuts CPA, Google maps AI shopping: Sept. 4

Reddit says its automated campaigns cut the average cost per acquisition, or what an advertiser pays to win one customer action, by 17% in testing. Google, meanwhile, is exposing more unpaid AI-shopping demand and spelling out how call and offline-sale tracking breaks. Today's common thread is simple: automation gets cheaper only when measurement stays honest.

Reddit opens Max campaigns to every advertiser

Reddit made Max campaigns available to all advertisers on September 3, after running the format in beta earlier this year. Max automates who sees an ad, which creative runs, where it appears, and how the budget is divided. Reddit says beta advertisers averaged 17% lower cost per acquisition and more than 27% additional conversions.

Those are platform-reported averages, not a forecast for your account. Still, the mechanism matters. Reddit can read discussion and interest signals that an outside advertiser cannot easily reproduce, then move spend toward the people most likely to act. That can lower customer acquisition cost (CAC), the total sales and marketing cost required to win a customer.

The danger is letting a cheaper platform conversion masquerade as a cheaper customer. An easy form fill can improve Reddit's number while adding low-quality names to your pipeline. Businesses with enough closed sales to feed a reliable signal should test Max. Smaller accounts should wait until they can judge revenue, not celebrate a thin sample.

Reddit also added asset groups, which keep creative and reporting separate by product or use case. Use that split to stop a strong product from hiding a weak one. The broader discipline is in our Google Ads budget-control guide: inspect what automation buys before increasing its allowance.

Google shows where products surface in AI answers

Google expanded Merchant Center's AI performance insights to Australia, Canada, India, and New Zealand, alongside the United States. The official report now shows how products appear for English-language shopping questions in AI Mode and AI Overviews, Google's generated answers inside search.

This is unpaid traffic only. Paid ads are excluded. Merchants can see their share of voice, meaning their share of appearances versus a Google-defined competitor set, plus common searches, shopper intent, and product details people request. That turns a fuzzy discovery channel into a product-feed job: missing size, material, or other attributes can now be tied to lost visibility.

Do not treat the share as revenue. Google says accounts without enough competitor data can display 100%, and recent information arrives with a delay of several days. Use the report to find missing product details, then judge the result in store visits and sales. Our analysis of AI Overviews and acquisition cost explains why these unpaid appearances matter as ordinary search clicks shrink.

Google clarifies the conversion settings that distort bids

Google added sharper instructions for phone calls and offline sales on September 3. Its conversion measurement documentation says call reporting must be enabled and the call action set as “Primary” for calls to guide bidding. Advertisers can also set a minimum call length, while Google assigns the result to the date of the ad click.

That date rule can make today's ad spend look unproductive while an older day receives the sale. Offline conversion imports, which send store or sales-system outcomes back to Google, take 24 to 48 hours to process. Google Click IDs, the codes that connect a click to a later sale, must be no more than 90 days old.

The costly failure is feeding the bidding system bad outcomes. Count every short call as valuable and Google hunts more accidental taps. Upload a sale under a mismatched action name and the system never learns from it. Set a call length that reflects a real inquiry, inspect individual durations, and reconcile Google's report with closed sales in your customer relationship management system, the software that stores leads and follow-up. Our small-business attribution framework shows the clean source-to-sale chain.

What to watch

• Watch whether Reddit's claimed cost advantage survives outside beta and after lead quality is counted.
• Watch Google add more countries or paid traffic to AI shopping insights. Either change would make the report more useful for budget decisions.
• Watch conversion delays around weekends and long sales cycles. A reporting lag can trigger a bad budget cut before the revenue lands.