DPS don't "have to do" anything. They can leave or kick dictators easily. Working as a group should be the rule for everybody, not just DPS. If some tanks or healers want to dictate, then good luck with that, they would be on most ignore lists in a short time :-)
I'd really like to agree with you on this but unfortunately you're lying to yourself if this is what you believe. Tanks, and healers are at a premium when it comes to Ops, and FPs. DPS are a dime a dozen. It is just the way things are. Tanking and healing are vastly more difficult than DPSing and as such the healers and tanks will be the defacto "co-captains" of any particular group.
If a tank or healer leave you will be waiting upwards of 15-30 minutes for a replacement in most cases depending on time of day. For DPS it is much more forgiving as they can usually be replaced in a matter of minutes even during slow times.
So DPS are at the mercy of the tanks and healers, or they will be waiting half an hour for another FP to pop. If you are a DPS and choose to ignore uppity, drama queen tanks and healers then good luck getting into ANY GF FPs, or Ops once you've ignored enough of them.