I believe ADI's question is just a result of knowing the segment of their market who attends the expo. ADI knows the high revenue integrators exist...they have them as accounts. The fact that their survey question has smaller revenue options on it is probably because their larger accounts do not attend the expo.
My guess is the larger accounts don't need to attend the ADI expo. Either their training is provided in-house and their technicians don't waste the time at the expo OR their training is provided directly by the manufacturer since they are such a large integrator. The training classes at the ADI expo reflect this...they are usually entry level classes designed to start you selling one product or another, and there is nothing wrong with that.
If you think ADI does not have large accounts over 1 million, I beg to differ. I can only provide one example but I'm sure there are others. I currently have a part time job working security on the weekends at a large pharmaceutical plant. My business is my weekly gig and I use the weekend income to pay off my students loans. The security integrator who services our plant is a very large company with accounts at concert venues, sports stadiums, and other pharmaceutical companies in the surrounding three states. Based on our contract, if they had only 10 other clients like us, they would easily make $1 million on service contracts alone. Do you know where their receipts come from when they install HES door strikes, Axis cameras, wiring, etc? That's right, ADI.
I think ADI is smart with their business model. They offer the convenience of a local branch with design assistance and other value added services. The prices are okay but there are breaks as you do more volume. As for the small integrators, I'm sure ADI knows that 1 in xxx will become that large integrator and I'll bet they will be happy to have started the relationship early when the integrator was making less than $100,000 a year.
I left this post as undisclosed not because I work for ADI or have any interest in them other than being a customer, but for the purpose of not disclosing the security company I work for nor the integrator that services them without their permission.