I don't have a problem with someone doing more boxes per se however the issue is how that CRHer does it. If they ordered that many from one bank at once.. the bank probably won't be too happy dealing with it unless they get something out of it. If someone keeps ordering 20 boxes, I can see at some point they'll stop doing it for them because the tellers will think what's in it for me? Theoretically, the tellers are supposed to do it anyhow because of customer service but the selfish human element of it always comes out. It's just better to keep it a lower profile and order from multiple banks rather than overloading one.
One big searcher isn't as bad as multiple searchers that pop up out of the wood work nowadays. The new influx of CRHers is what is ruining it. If it continues, I can see this hobby going down the tubes.