Well Steve, I wouldn't doubt if Wertheimer actually did take around 3000 photos of Elvis.
Remember he shot Elvis at three occasions, Dorsey shows on February 4 and March 17 and then we have the week from June 29 thru July 4.
The first time around he probably didn't shoot more than 3-4 rolls of film. With Elvis getting more and more popular with each Dorsey show he might have used at least 2-3 times the amount of rolls in March and then he followed Elvis for an entire week at the very peek of his career. Rehearsing for the Steve Allen show, on his way to Richmond, all day in Richmond, on his way back to N.Y. dress-rehearsal for Allen show, the actual Allen show, in the studio on July 2, all way from N.Y. to Memphis on the train, at Audubon Drive and finally at the show at Russwood Park on July 4.
No Steve, I don't think the number of Wertheimer photos is too far fetched from reality. You also have to keep in mind that a real big number of these photographs might not be of such quality that they're fit for publishing.