there's no rule that says you have to respect someones opinion. you should; however, keep your opinion on someone elses opinion to yourself at times. i don't respect anyone's opinion when they talk shit. it's like respecting a guy that goes around and trashes on people for the way they dress.
Yeah it is annoying when people trash on other peoples style, but you have too deal with it. You cant only acknowledge the opinions you agree with, not everybody is gonna think youst like you in every matter. Thats why its called an opinion, they can choose too believe what ever the heck they want too believe in, and you youst have too deal with it. Ignore it as you will, but respect it.