Image titles tend to do decently via book market and unlike superhero titles, they tend to sell past new comic Wednesday. Image seems to operate more similarly to traditional book publishers than comic book publishers. I'm guessing Image titles have fairly decent long tail via digital, too.
http://www.jimzub.com/creator-owned-...the-long-tail/
For 2016, there were 804 Image books that sold a total of 278,661 with total retail value of $5,350,089 that didn't make it to the Top 750. For 2015, the top #750 title sold an estimated 3,475 copies and for 2016, the top #750 title sold an estimated 4,053 copies. These are estimated sales to customers and includes data from Amazon, Barnes & Noble and Walmart. It does not include sales to libraries, Scholastic book fairs, etc.
Gotta say, wow, Kirkman's book market sales absolutely demolishes combined sales of TWD floppies and GNs via the direct market. Granted, the TV show and product licensing deals probably make him a lot more money than all the books do.
2015 BookScan Top 750 - Image Comics
AUTHOR # OF BOOKS EST. UNIT SALES EST. RETAIL PRICE KIRKMAN ROBERT 40 522,371 17,603,181 VAUGHAN BRIAN K. 6 171,659 2,756,718 REMENDER RICK 4 29,008 317,390 GILLEN KIERON 2 25,036 292,895 WIEBE KURTIS J. 2 23,489 289,495 FRACTION MATT 2 23,231 282,638 SEJIC STJEPAN 3 15,769 236,377 SNYDER SCOTT 1 14,683 146,683 ADLARD CHARLIE 1 3,697 129,358 DECONNICK KELLY SUE 2 12,479 124,665 HICKMAN JONATHAN 2 9,670 116,453 AARON JASON 2 7,782 77,742 LEMIRE JEFF 1 7,379 73,716 ELLIS WARREN 1 4,078 61,129 BRUBAKER ED 1 4,026 40,220 BUSIEK KURT 1 3,905 39,011
2016 BookScan Top 750 - Image Comics
AUTHOR # OF BOOKS EST. UNIT SALES EST. RETAIL PRICE KIRKMAN ROBERT 40 525,153 17,787,624 VAUGHAN BRIAN K. 9 193,838 2,892,207 WIEBE KURTIS J. 3 30,562 405,579 GILLEN KIERON 4 29,833 400,106 REMENDER RICK 4 26,182 287,313 LIU MARJORIE 1 24,128 241,039 LEMIRE JEFF 2 19,654 232,504 FRACTION MATT 2 11,576 147,229 HICKMAN JONATHAN 2 9,259 115,947 DECONNICK KELLY SUE 1 10,328 103,177 SNYDER SCOTT 1 9,913 99,031 YOUNG SKOTTIE 1 8,424 84,156 SEJIC STJEPAN 1 4,779 71,637 ELLIS WARREN 1 5,026 50,210