Northern Ireland international McAuley, 32, has played a key role in establishing Albion in the top flight via his partnership with Jonas Olsson at the heart of the back four.
But McAuley's entire career was spent outside of the Premier League before Roy Hodgson brought him to The Hawthorns on a free transfer from Ipswich 18 months ago.
Clarke believes there are other bargains to be found in the lower leagues but that there is a reluctance from some clubs to delve into that area of the footballing pyramid.
He said: "When you see how well Gareth has done, and how well he's acquitted himself to the Premier League, I am surprised he stayed under the radar for so long.
"Is there a reluctance to take a gamble? I don't think there is a reluctance on the part of our club, but maybe from others.
"Some of the bigger clubs, in inverted commas, look elsewhere for their talent but it is possible they are missing out on a good find from the lower leagues.
"I think the example of Gareth also gives hopes to people in the lower leagues.
"The players that have been stuck down in the lower leagues for ages may think there's not a way up - but there is a way up. If you get the breaks, Gareth has shown you can do that."
Clarke added: "If you watch Gareth week in, week out, you can see what he brings to the team. He's a good, honest, old-fashioned central defender.
"He puts his head in where it hurts, wins his tackles, makes his interceptions and keeps the game simple.
"He's got a real hunger because he did come into the game late and he's got his chance at the top level late.
"He's got a real hunger and desire to do well every game and that's a fantastic attribute to have."
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