We have seen some advertisers display wrong URLs in display URL but when we click on the URL it goes to a page completely different from what was mentioned in the URls. We reported some of these competitors and Adwords team did take things seriously and removed those ads or replaced them with them with the correct ads.
Advertisers do this mostly to cheat the Google's policy on 1 TLD URL per list of sponsored results. Say there are 10 affiliates having different IDs pointing to the same Merchant Google's policy is to allow only 1 affiliate mostly the highest bidder. To cheat this webmaster have a wrong display URL thinking that Google will ignore them. Now adwords quality team is very strict on this and they disallow ads doing this

PPC Management Team,

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