J.,
It's not the tonsils so much as the adenoids. The adenoids are like a giant tonsil at the back of the nose/mouth- you know, where it gets all itchy or sore when you're sick but you know it's not the tonsils? Well, in some folks- my family for instance- the adenoids are enlarged, acting as a jumping off spot for bacteria right into the eustachion tubes.
My girls got into this mess and started having hearing loss due to fluid buildup, plus snoring (sometimes goes with). We opted for tonsils and adenoids out in one, and just the adenoids in the other. They have never had dairy, or that would have been my first move- it causes mucus to be stickier and more abundant, which makes it likelier your kid will get bacteria hanging out.
I definitely believe in the ear-pulling and adjustments- even a massage therapist can help dramatically, but in some cases the chronic nature can call for dramatic treatments. In any case, anyone thinking of tonsilectomy should ALWAYS get the adenoidectomy at the same time, as they cause problems later in life, too.
Best of luck!