Yes, but you ARE judging people based on their tolerance toward homosexuals. If I said I thought homosexuality was a sin and homosexuals should be locked away, you would judge me as "evil" for my viewpoint.
There is nothing wrong with making judgments on people based upon the information you have about them. You can make judgments that are too rash or general to be useful, but you still make them. The important thing is the way you act upon those judgments or how you follow them up.
To me, people who DON'T voice their concern over the treatment of homosexuals are actively assisting in the struggle to stop equal rights being granted to a large part of the population. It's as simple as adding a "gay rights" check box to your voting criteria when selecting a candidate. It's as simple as writing to your governor telling them you want equal rights legislation passed (mine said, "No thanks"). It doesn't have to mean you do anything evil to someone else. It just means you take a stand for what is just.