...from the part-time job, reasons non-native English-speaking people don't like reading science fiction (and my retorts in parentheses):

"it's a man's world in my eyes" (The Gate to Women's Country by Sheri S. Tepper or The Terrorists of Irustan by Louise Marley)

"it's almost always not real science" (Blood Music by Greg Bear)

"it doesn't teach any lessons we might need in the future" (Beggars in Spain by Nancy Kress)

"they make me afraid because I don't like robots and technological stuff" (Lion's Blood by Steve Barnes)

"the science is confusing and I don't understand" (Uglies by Scott Westerfeld or Life as We Knew It by Susan Beth Pfeffer)

"science fiction books always talk about a depressing future" (The Dazzle of Day by Molly Gloss.

"science fiction books just aren't real...it has nothing to do with reality" (Andromeda Strain by Michael Crichton)

Now, one must keep in mind that definitions of what constitutes "science fiction" differs by country. For example, in Japan, what we might call science fiction is sometimes shelved with thrillers or mysteries. However, it did kind of get my dander up to hear all these people dissing SF.