Someting like 60 PERCENT don't vote for exactly those reasons. And I believe a lot of them are VERY interested in The Donald. Even ten percent of them make it a blowout.
About 60 percent don't vote. But, I don't think all of them fit in the "don't like the choices" group.
I'll speculate on of some of the larger subsets of the non-voters, in no particular order:
I'm sure that you could come up with more categories.